I used to, but stopped as it's much easier and I haven't experienced any negative effects since doing it. I toss all of the hops in loose, chill, stir, let settle then open the valve and right into the carboy. Usually the most trub comes from the very last bit of volume, but if there's a lot mixed in with the remaining wort, it goes right into the carboy with the rest. The only real issue is with my IPAs and that I lose an additional 0.5-.0.75 gallons of final volume due to all of the hop matter, but that's negligible overall. I'll probably just to 6 gallon batches of IPA/DIPA for 5 gallons of final volume.