+1 to everything Bug said (except, he might be just a bit lazier than me
). Has your beer been sitting on the dry hops for 2 1/2 weeks? If so, that could lend to a grassy and/or vegetal flavor. If not, RDWHAHB
I skip secondary for a couple reasons. One is that too many times folks will rack to secondary too soon and then gripe about low attenuation and/or esters.
Diacetyl is another one I see/hear a lot. Most of these problems can be tasted at the time you rack, so if you insist on a secondary always taste before transferring.