Back in the day when I fished gear I used to catch almost all my fish on flies under the float. I did better with them than goo, yarn, and single eggs put together. A big part of why I went fly only really.
As for it not being "fly fishing" I would have a few reservations about that moniker. Ever see them boatmen patterns that are basically a piece of Styrofoam and you colour them with markers? Yup, a fly.
What about gummy minnows? Yup, them's a fly too.
Flies these days a lot of the time are made up of artificial materials more than anything else.
For fly only systems the only thing that needs be done is get rid of the float/shot and stick the egg on the hook. In many ways the trout beads can out last Jensen eggs as they never go milky.
Now with all that being said I chose to leave them on the shelf. They simply aren't "fly enough" for my liking and I use stuff called Egg Foo Yarn. This stuff makes quick easy painless egg patterns with no muss or fuss.
Not a judgement call or ethics department baloney just my preference.