Let's say you have already put your beer into your fermenter and you decide its taste is not hoppy enough. So you start out to add some more hops into it. One way to dry hop, but I will not expand concerning it. The method I would like to discuss is boiling your hops in a small amount of water, waiting for it to reach room temperature and then pour your "tea" into your second fermenter before you close it. The question is: how good are the results of this? Do the same boiling rules for hops appear here too (ie, 60 minutes for bitterness, 30 for flavour or 15 for aroma)?
One technique with the hop tea would be to maybe hop burst it. Where you boil say 4 oz for just 10 minutes. There will be some complete conversion to bittered iso-acids, just not much in 10 minutes. Hence the use of 4 oz and the term bursting. The downside to this is that you are also going to bring along ALOT of hop aroma and flavor. Which might be fine or bad depending on the style being amended.
I thought BYO magazine had a story last year or the year before where they talked about making hop tea to increase bitterness. But I couldn't find a link. Maybe if someone else finds it and can put it in as a comment.
If all you want is to get some more bitterness in your brew using some isomerized hop extract may be be a better method. I have a couple brewing buddies that have used it with good results.