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Apparently you haven't been following the discussion about SRB safety nor has it even occured to you that there is another and very important variable to consider when designing rockets..."/quote

What discussion: I joined under two weeks ago. Still exploring the site for interesting threads.You're making assumptions on the basis I haven't mentioned other factors. That does NOT mean I 'm not aware of any/them.

Quote/ First of all, the Shuttle SRBs, by virtue of their fuel blend  have a handy little characteristic: if they leak, they stop burning. The solid fuel only burns rapidly when it is under pressure, so if there is a leak the pressure drops and the combustion slows down. Solid fuels themselves also cannot explode, since the rate of combustion is intrinsicly controlled by the surface area. Modern solid fuels are imbedded in hard rubber, so there is no possibility of a sudden radical increase in surface area or burn rate. Pop-off caps using venerable explosive bolts on the sides would also provide shut down options."

Oh yes they can explode matey! Ask any Range Safety Officer! PBAN is as volatile as any other SP in the right circumstances. And it is by NO MEANS a new SP combination. Use it myself in my own H-PR's. LOT's going for it. You would need a pretty substantial "leak" to engender the pressure drop characteristics you describe: and they would by no means be consistent. In any case that pressure you speak of is a function of propellant burn, and the surface area as we both know, constantly varies, hopefully with some consistency - mute point , since it usually doesn't, which is why a large performance margin in the SRB has to be catered for elsewhere. Actually the rate of combustion depends upon the burn occuring over the entire constantly varying internal surface area from top to bottom; in effect enlarging the central hole once the star-spigots burn off; in the initial stages. Which, in of itself,implies a pressure drop through increased csa! Hence the regressive thrust characteristics of most solid motors, except those employing a 'D' core design.  That asymmetric design also has it's risks...
In any case, as we saw from Challenger, a leak DOES NOT prevent a solid motor from continuing to burn. If it did, the effect in of itself could result in a CATO. The other one is still burning...get it...? Granted that wouldn't apply to "The Stick", but certainly to Ares 5...

QUOTE/ Second, thanks to their sturdy steel construction, if there is a leak around
a segment seal it won't lead to a catastrophic explosion like smaller light-weight SRBs. The SRB has sufferd at least two leaks, first with Challenger and a second with Atlantis, but in both cases the SRBs did not explode. In the latter case Atlantis was able to continue on to orbit as the leak didn't face the tank or orbiter."

Do remember that a solid motor is intrinsically a controlled explosion in of itself. Explosive gases seek the path of least resistance first, so your thrust vector takes on an asymmetric characteristic which has the potential of becoming uncontrollable. It is just that "sturdy" construction that give the segmented SRB it's low structural efficiency. It is the marginal performance predictions that require compensation in the other stages for M.O.E purposes.

Quote/Since the CEV and its upper stage will be riding on top of the SRB's one-piece steel end cap, no segment seal leak can threaten it. If there is a leak, it will also be obvious and easy to detect since there would be a sudden loss of thrust.

A very good argument for the fallacy of the side-by-side booster/payload configuration! Nonetheless, I don't agree for reasons iterated earlier.

QUOTE/Compare this with a liquid engine, any liquid engine, and these are compelling advantages. Reguardless how its arranged, liquid fuels will always have the possibility of exploding, while the solid fuel doesn't. All modern high-performance liquid engines are also turbopump driven, which carry inherint and "unfixable" safety concerns. When they fail, they usually fail big (maybe ignite the fuel too), and it doesn't take much to tear up a turbine spinning thousands of RPMs cooled to cryogenic temps.
Many high-performance engines also operate at very high chamber & nozzle pressures/temperatures that stretch materials to the limits, increasing the risk of catastrophic failure and the severity of the failure if it does occur. Liquid fueled engines are also much harder  to instrument and monitor to provide sufficent warning to shut down or use the crew escape systems, there is little warning when a turbine is about to come apart and monitoring the temperature all around the nozzle would be difficult."

Known quantities(for decades), and characteristic of ALL liquid motors including the J2-X and CEV PM of the ARES 1 &V upper stages. But I would remind you that both the Saturn's SI-c and Blue Streak booster stages each had a perfect launch record. As for the instrumentation; standard stuff! How do you think they evaluate Test Flights;guesswork? Just image the SIZE of the vehicle if THOSE were solids for just the very reasons you've outlined. A falacious argument at best. To my mind, the solids are an okay solution, but in terms of optimum performance/overall cost, don't cut the mustard.

QUOTE/ Eliminating the possibility of these occuring with added headaches involved with man-rating and instrumentation in one of the two stages of the CLV is a major bennefit. There is one more bennefit that SRB has that isn't technically related to the engine, that is because of the very high thrust the CLV can accelerate more quickly than an EELV-style liquid fueled rocket which improves the safety by getting off the pad and to orbital velocity faster."

That high thrust only lasts for so long - in the initial stages - such that SRM stage burn-out velocity is usually 1000/1500fps down in deltaV in comparison with a LP Booster, leaving the upper stages with much more work to do.  More than offsetting the high initial acceleration:which is merely a function of Thrust to Weight ratio in any case.

QUOTE/This is good, especially for ISS missions, since if you have to ditch in the sea you can do so closer to shore and further south in warmer water than if you accelerated slowly, plus if you get pretty close to orbit the CEV's extra fuel might permit a once-around abort that avoids a hypersonic backflip in the atmosphere with normal parachute deployment in the US."

"Uh Huh"! By the way, the ditching criteria is as much a function of the trajectory parameters as the launcher characteristics itself; particulary with respect to hi-LEO ISS type orbits, where a steep trajectory is employed with downrange distance being markedly reduced.
An atmospheric "hypersonic backflip"!? Do me a favor! A partial orbit scenario has been/is built into every manned launch trajectory in both the U.S and Russia(I remembered!) from the beginning. Even if Orbital Velocity is not achieved, a spacecraft will re-enter much as an ICBM would - with possibly more control. 

Your other points aside, the leak/outgassing from the segment joint on Challenger began 180degrees away from the ET/Orbiter also. All the video footage shows that. Which was why I began thinking NASA's explanation of the incident was suspect. As with Columbia, where the video clearly shows the eco-foam chunk hitting the wing well abaft of the lower leading edge and disintegrating down the underside of the wing. Whereas the "experiment" clearly was a direct hit upon the upper surface  the wing leading edge itself.
As for your point re the time to orbit, any advantage of initial acceleration is more than offset by the intrinsic long burn time of the J2-X  LOX/LH2 stage which burns out at only 63miles altitude, leaving the CEV propulsion module with some 120 miles of altitude to gain - 65% of total: in vacuo, granted. No indicator of the deltaV component required. Most orbital trajectories make the penultimate stage achieve the highest altitude fraction, with - 3+stage configuration - the final stage(s) merely doing kicker duties with usually only a slight altitude gain.
I haven't plugged ARES 1 into  my software yet, since accurate mass fractions/structural efficiency and RSRB criteria haven't been provided on the data I have access to(unless the original RSRB is being ressurrected..right! Fudge factors! Why not! Mark Wade to the rescue!), but the CEV PM must have massive reserves to achieve such a huge climb all on it's own.