Ok, just to bring the point home after seeing all of these home made gizmos's that take all kinds of work/time.
A socket on a breaker bar laid against the floor...doesn't matter if left/right thread just lay it in the appropriate direction.
Bump the starter....no bang, no explosion, no moving breaker bar, just a loose nut.
Believe me it is a non event...I've done this on my TR3 and V8's with huge horsepower...works the same either way.