"There is some debate about how deeply primers should be seated. I don’t pretend to have all the answers about this, but I have experimented with seating primers to different depths and seeing what happens on the chronograph and target paper, and so far I’ve obtained my best results seating them hard, pushing them in past the point where the anvil can be felt hitting the bottom of the pocket. Doing this, I can almost always get velocity standard deviations of less than 10 feet per second, even with magnum cartridges and long-bodied standards on the ’06 case, and I haven’t been able to accomplish that seating primers to lesser depths."
Dan Hackett
Precision Shooting Reloading Guide, Precision Shooting Inc., Pub. (R.I.P.), Manchester, CT, 1995, p. 271.
So I think were can infer a potential test from that. It suggests that if the floor of the primer pocket isn't firm enough, SD may increase. If SD increases, it isn't just the speed difference in the bullet itself, but it usually indicates varying ignition delays which, if they are great enough, will allow small movements to shift the muzzle differing amounts before the bullet exits. So, have at it!
Incidentally, it is the citric acid in lime and lemon juice that does the polishing, and it is a lot cheaper than the juice.
10 lbs is under $25, postage paid. I've had good luck with that source in the past, but there are others.