>What is this, I've never heard of it? Are there significant benefits?

Nobody to block your transfer and freeze your accounts simply for the reason you look suspicious and you are suddenly transfering a 10 digit sum to a *stan country.

And even if a higher tier bank with whom your own bank has a correspondent account will bother to intervene (which is highy, highly unlikely), you and your moneys will already be far away from the sphere of influence of the civilised world thanks to the fact that transaction settlement is nearly 100% automated and instantaneous for top tier banks.