professor beer said:
My take on this after trying both at various stages of the brew is:
Aroma and taste seem to be best achieved by a strong hop tea added with the hops in it, a day or 2 before bottling/kegging. Dry hopping in the fermenter is a waste of hops as the CO2 dissolves the aromas and you loose it, dry hopping in the conditioner doesnt yield much either as you need loads of expensive hops that mostly float on the surface so only half the hop flower is submerged and the lower temps do not favour infusion.
The genius that is Thornbridge have invented something called a hop cannon which I would love to know more about if anyone has some inside information.
If you use a hop bag, it should be weighted so that the hops are submerged (but ideally still with some space in the bag to get exposure). Loose pellets, which I like using too, sometimes need a gentle push to get properly wetted and submerge, but can produce terrific results given a few days (sometimes up to a week, I've found) to fully sink.
As regards temperature, I recently racked my Galaxy to a secondary when the gravity was low (1.009, after a week) but not quite stable, chucked in 50g Galaxy leaf in a weighted bag, kept it at 22C for two or three more days, before chilling down for another 5 or so and bottling (1.008 by then). It's got a cracking amount of Galaxy aroma. I wasn't aiming for a total hop bomb - just 100g Galaxy in total, though all from 15 mins onwards - but I'm pretty sure I got good value out of what I used.