Most of my transactions are going the opposite direction. I always go from SR-torenabled wallet-to mtgox thru tor enabled wallet. It would very difficult to show that btc came from sr. Granted, you can always use that btc tumber, but as long as your not running big numbers in any given day or month, you should be ok. Now, going directly from SR to MT Gox isnt a good idea (going both ways) Even though sending btc from SR to a tor enabled wallet really isnt tumbling, i call it a poor mans way of tumbling. Also, It may be a good idea to access MT. gox from a library or a public place. Also, make a couple of Mt. Gox accounts and transfer it from one to another or go to/from liberty reserve. If I use my computer to access mt gox from home, they will have my ip address. but, they would have to prove that the btc came or went to/from silk road. (which would be tough to prove if you are using a tor wallet) I also do a couple of other things that I wont share publicly, its a good idea to keep some things a secret... Adding layers of protection is always a good idea.