It seems to me like it wouldn't work - you're basically just adding a single hop between the stolen coins and you...
Even if you consider the simplest case, address A (clean) and B (stolen) put their money into address C, and then split them into addresses X, Y, Z, you already can't tell where the stolen money went.
Now do that multiple times with randomly generated address, random amounts, it becomes indistinguishable from regular transactions. Everything blends together.
1) Governments know that criminals use tumbling services, so there is a non-trivial chance that tumbling services are actually honeypots run by LEO's. If you think LEO's are not smart enough to think of this, consider freeway DUI checkpoints: a huge flashing sign across a freeway announces "Warning: DUI Checkpoint Ahead - Prepare to Stop." If you stay on the freeway, you'll notice that you never see any DUI checkpoint. The checkpoint was actually at the end of the first exit ramp after the sign - placed there to catch the fearful drunks that take the first exit after seeing the sign. (Frankly, I'm suspicious of publicly-available VPN's like StrongVPN for the same reason.)
2) Once your coins are tumbled with the coins of other criminals, the coins you withdraw from the service are associated not only with your own crimes, but also with the crimes of all the other criminals using the service at the same time.
If I understand correctly, you can spin up many bitcoin wallets.
Wouldn't it be possible to create a bunch of Bitcoin wallets that would trade money amongst themselves?
(Or did I just re-invent the tumbler?)
1) You need "clean" money to mix with, as in different from stolen.
2) Tumbler service is more fee-efficient, because they do it on a large scale, and can do many transfers in one transaction.