+1
So, another question is this: Which is more difficult, tying a dropper to the eye or bend of the hook, tying a dropper above a knot, or adding a mono loop to a fly while tying.
IMO, it seems like you're solving one problem and creating another. The stronger the mono loop, the more time to tie the fly (additional thread wraps and glue) and the more it will limit fly action/movement.
As a winter coping mechanism I've though a lot about what triggers a fish to eat an artificial fly. Movement, i think, is a key trigger. So, anything that may limit that movement such as tying a dropper to the hook in any way may limit overall fly movement. Material micro-movements (think "soft hackle") are a different topic.
Look up Kelly Gallup's dropper nymph system on YouTube for the detailed rational behind this and how dropper attachment affects it.