I guess one way to get around any interference would be to have the sending bank convert the USD into a different currency in house before sending the wire.
For example a Japanese company that deals with a lot of foreign transfers could convert a USD payment into Yen and then wire the Yen to the recipient where it would be converted by the receiving bank into the accounts native currency. This would probably cost a bit more though.
So, to take the case of a Mt Gox withdrawal (or deposit), if you withdraw or deposit in either your own country's currency, or in Japanese Yen, then although the transfer might still go through an intermediate bank, if it does then that bank will
probably be either in your own country or in Japan.
If you do the transfer in a third country's currency (such as someone in a country other than the US or Japan doing a transfer to/from Gox in USD) then the transfer will
probably go via one of more banks in the third country.
One
might argue that involves an increase in jurisdictional risk (the transfer is now subject to three jurisdictions rather than two). Whether in reality it increases the risk of the transfer is less clear.
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