At a technical conference a few years back, I decided to give my presentation using hand written viewfoils on an overhead projector. The conference venue had to really dig to find a working projector :-) For years afterwards, people would come up to me and remark on how that presentation stuck in their memory! (I still have a mechanical typewriter. Maybe I won't throw it away after all.)
A friend of mine fell when going on stage for a conference. He broke his nose and there were lots of blood and an ambulance involved. Everybody remembers it. It's great that you use that technique if it is going to make your presentation clearer, if using the projector really helped your audience to get whatever you were presenting better. If that was the case, congratulations for an original idea. But if they only r…
It didn't affect the content of the presentation at all.
The only issue was one of perception - I was talking about new technology, and was presenting using old technology. It wasn't congruent, and didn't really fit, although it was fun. Hence it was a one-off thing. I didn't do it again.
I doubt today one could even find a viewfoil projector, and the audio-visual staff would be annoyed because it won't interface to their recording system. Annoying the AV staff is never a good idea.