Reports from powder manufacturers, ammo makers, military, home experimenters have no effect on this debate. It has been going on since I started frequenting forums years ago, and it still comes up every couple months or so. Seems to break down into two schools; No, the tumbling will break down the powder changing the burning rate, and a primer may get hit hard enough to fire while tumbling. And Yes, ammo manufacturers tumble their newly manufactured ammo, and the military ships ammo all over the world in planes, trucks, jeeps, on donkeys, and are subjected to extreme conditions of vibration/jostling and temperature, with no effect on ammo preformance.
No amount of evidence on either side will solve this debate. It seems to have a life of it's own...
BTW; I don't tumble my finished reloads ONLY BECAUSE THEY AREN'T DIRTY!