On the topic of hop aroma, do people find that they get different hop character when dry hopping at different temps. It could be all in my head, because the difference isn't huge, but when I dry hop at lagering/kegerator temps, I swear I get more grassy flavors than dry hopping at room temperature.
Everything stated below is my own experience and is not a suggestion that it will work for you. If anything sounds fact-based then dismiss it because it is not:
I've personally experienced the same grassiness from cold temperature dry hopping, and I've concluded that it's simply a function of temperature and time. Just like hop storage can be improved 10-50x by limiting oxygen, light, and freezing temperatures - but eventually they will lose their muster just like everything else. So, I find that 5 days of room temperature dry hopping is equal to about 30 days of cold-serving temp dry hopping, which is to say that you'll find the same level and character of grassiness on days 1-2 at room temp dry hopping that you'll find in 1-12 days of cold-temp dry hopping. As you move beyond those 12 days, the grassiness begins to fade away leaving the nicer characters of the hop; and by about day 30 at cold temps nearly all of the grassiness is gone leaving behind only the qualities you are generally striving for. So, that said, when I keg hop my beers I will leave them at room temp (65-70) for 5 days before putting the keg into cold storage and that solves the problem for me.
Yeah, that's my feeling, too. I think you get through the grassy period much quicker dry hopped at room temp, which is why I do it most times. Just IMO, etc.