Aw heck, nobody gets them that accurate with a feeler gauge anyway.
Unless you are Spiderman with super senses!
Agree though, no way, no how is a feeler gauge going to get it as accurate as a timing fixture.
That being said though, I don’t think the average guy, with 1 motor should buy a timing fixture, for that use a feeler gauge. But if you are going to get into this hobby, and get a couple motors, fixture is a great investment! Ill never go back to feeler gauges again.