And as fast as I typed this in, another possibility came to me in that it doesn't really matter when the C6s 'shut down'. The act of booster separation could simply "release" the three strap-ons simultaneously, thus negating the residual effect of the extra thrust. The thrust from the three strap-ons would "die" at the same moment as the booster itself.

The added visual effect of the three strap-ons "peeling away" like from a Delta would also be"veer-ry een-ter-resting"...


Craig...