What would have been really cool as a backup plan is that someone else that he really trusts had access to a copy of wallet.dat with the 26,000 bitcoin in them.
And now that the is arrested he could tell that person the password so they are transferred out of that wallet that the FBI has "confisquated"
My understanding is that th FBI "moved the coins to an address under their control". But that would have been a savvy backup plan.
Yep. The 26,000 were the BTC in escrow. The keys for those addresses had to be on the server because the payment process was automated. While SR staff had access to the server, the feds had a protective order authorising them to sweep coins from the escrow accounts (and any other accounts identified as belonging to the defendants) into an address controlled by the authorities.
It didn't matter whether someone else had a copy of the wallet.dat because that "someone else" wasn't aware of any need to move the coins prior to the domain seizure notice going up - the same protective order which authorised them to seize the domain authorised the feds to move the coins. It also authorises them to sweep any coins which continue going into the SR accounts (ie, coins from transactions pending) before shutting down the SR servers. 3, 4 and 5 are the relevant parts of the protective order.
http://www.nytimes.com/interactive/2013/10/03/nyregion/03silkroad-documents.html?_r=0
