Decap with a unversal decap die first, then clean/tumble and resize.
Four reasons I do not agree with this and can't recommend it:
1) when you decap BEFORE you tumble in a vibratory cleaner, you don't get the benefit of clean primer pockets because even tumbling won't clean those little pockets. (a sonic cleaner in liquid will)
2) you end up with corn media sticking in your primer pockets and flash holes. Not in every piece of brass, but in some -- and a piece of media stuck in either of these places can & often does displace or snap a decapping pin later when you attempt to resize
3) decapping before tumbling in a universal decapper adds a whole 'nother step to the process, and that's a LOT of work as the number of cases increase. That's one more hand motion in to a shell holder, ram up & down, and case out of a shell holder. For no benefit?
4) disagreeing with anything wncchester
posts is always good for some thread fireworks.
Even if you try to let him know it's just friendly ribbing!