For Muenchian grouping examples, just google Biztalk and Muenchian.
Recoverable processing is a mechanism for processing a batch of messages and only failing the bad ones.
On Biztalk 2004, if you had a batch of 100 messages, one of which was bad – all 100 would fail.
With Biztalk 2006, you can turn on recoverable interchange processing so the 99 good messages are processed and the one bad one is suspended.
This is optional, it may not be what you want to happen. If for example the sending system is unable to handle individual failures and must reprocess the entire batch, then you would not want to use recoverable interchange processing