A form of cover that doesn't get you busted by the feds and thrown in jail?
Let's say I'm an expert killer who has assassinated dozens of people without being caught. Do I camouflage myself by doing a shitty job and getting sent to jail? Of course not, I keep doing an expert job because I'd rather not be in jail.
There is nothing inherently illegal about creating BitCoin but there is something very illegal about facilitating drug trafficking. If they were the same person, wouldn't you practise good OPSEC to keep you out of prison? What is the value of keeping your identity as BitCoin creator a secret when you are in prison?
If they were one and the same, it seems to me, you would just practise good OPSEC across the board or, if need be, make "mistakes" that reveal you as BitCoin creator (and take the credit) and keep your identity as SilkRoad founder a secret.