I started stripping 5 coats of paint off a 1912 porch floor in 2001 and it has been a nightmare.
We do not have lofty notions of this floor having a refined look. The paint color most absorbed into the wood is a gray blue and we hoped that by staining or painting the floor a dark brown after adequately it would hide most of the imperfections.
I've used stripper which was NOT effective and a heat gun which has been the most time consuming but helpful and a big sander. At what point do I have enough paint off to stain or paint over?