[Boundless]

>> the booster can be safed before it causes a total
>> loss of the stack.

> If you have to shut down the engine, you've lost the rocket.

Sure, but not necessarily the crew. Which is the whole
point on a manned vehicle.

>> ... only works reliably if what you are blasting away
>> from isn't still accelerating toward you

> Nah, the acceleration rate of the rocket is well known.
> The escape rocket merely has to be designed to exceed
> that. There's no guess work involved.

My back-of-the-PostIt-Note estimate says that no escape
rockets, tugging a capsule, can out-accelerate a stage 1
under full thrust. And building one that could would be
needlessly consumptive of otherwise valuable payload.

[Cincinatus]

My back-of-the-PostIt-Note estimate says that no escape rockets, tugging a capsule, can out-accelerate a stage 1 under full thrust.

I guess they were just wasting their time with these vehicles then...

[RightWhale]

The escape rocket is vectored along a path away from the direction of the launch vehicle. In the case that the launch vehicle is rotating and going in unknown directions, the vector of the escape system could be anything and the result would be successful unless the booster happens to veer in the exact wrong direction at the wrong time. Odds of that are very small.

[null and void]

And building one that could would be needlessly consumptive of otherwise valuable payload.

As opposed to sending a brickyard into orbit?