After hundreds or thousands or maybe only a few dozen loadings they end up with the rifling ends battered at the muzzle and so ruining the barrel's accuracy
I use short starters...and admittedly as bad as that burst barrel situation was, plan to continue using them for two reasons:
1) I do like a snug P/B combo, can't start them without a short starter;
2) To eliminate any chance of "wallowing wear" at the muzzle...AND/OR...deformation of the projectile.
(PS: the SS's I use at the range even have captive muzzle guides on them).
IMHO...as unfortunate as the burst barrel incident was...and all these discussions are excellent to re-emphasize an awareness level to all of us...there is never-the-less a degree of danger inherent in this sport.
The constant proximity & use of black powder;
Blowing down a barrel or not;
Wiping between every shot or not;
Using a short starter or not;
Actually seating the ball over powder;
Allowing auto-priming or not;
Pouring water down a bore and waiting 30 minutes before pulling a ball or not;
Using a hammer stall or not;
Etc;
Etc;
The list goes on and on...
I operate within the sport as safety conscious as I know how within the realm of practicality and calculated risk...ie: if I NEVER EVER wanted to be exposed to any risk from this hobby, then I would end it today...the same could be said about driving to work every day...to literally remove every element of risk, I'd have to stay off the highway.
On the lighter side...lets think outside the box...how about this:
We imbed a micro chip in the range rod where the witness mark is located...and when the chip comes into magnetic proximity of the steel muzzle...a release mechanism on the lock is actuated which only then allows the frizzen to be closed to take a shot.