Don't ever feel stupid for wondering; this question is very pertinent. I don't quite understand what you mean by a "sharp" trip, although I find taking off my glasses to be actually more enjoyable visually.
On my first nutmeg trip, I had eaten the nutmeg an hour before going to sleep. Since nutmeg kicks in fully only after ~6 hours (and lasts up to three days... weird stuff), I thought it didn't work... I woke up nutmeg-high and confused, and forgot to put on my glasses. Everything looked much more fuzzy than when I normally don't put my glasses (but I usually NEVER forget my glasses), and it made me very euphoric when I realised the nutmeg had worked finally. So I spent most of the day without my glasses, when I usually can't live without them for five minutes.
I also find that the DXM visuals are more enjoyable without glasses. DXM visuals are made of sensory input that slowly drifts into something else, and not having my glasses made that process much easier. Damn, was that TV static fun to watch.
Finally, my last LSA trip was mostly spent lying on my bed (I should have extracted the LSA from the Hawaiian Baby Woodrose seeds, it would have spared me the nausea). When I didn't have my glasses on (most of the time), it was easier for me to concentrate on what little visual effects I had (color bleeding, patterns moving, lines blending). Also, not seeing my bedroom ceiling clearly helped me travel mentally and introspect (though not as much as with my eyes closed, but I could look at the pretty effects at the same time).
As for the lenses vs. glasses debate, I definately reccomend glasses over lenses. You can take off or put on glasses quickly, and that's great when you're tripping since you never know when you'll want to lie down or get moving. Glasses also won't dry up on your eyes if you forget them on your face, and they're easier to pick up if you dropped them.
Anyway, I encourage you to try both if you can, and do what you feel more convenient or comfortable, since these are quite important while tripping.