[fel64]

There is one thing you can do – there’s a generic query filter that executes every time bbdb makes a query. You could use a regex to get the thread numbers from that. (If you don’t know regexes that well I could write it.)

Probably no design decision behind that, just an oversight. Go to trac, log in using your details here and create a new ticket requesting this (marking it as an enhancement not bug). Mdawaffle (^^) is busy with wp or something at the moment but when he sees it he’ll probably either implement or discuss at least.