Need to level OSB board for LVP, pros and cons of using roofing shingles?
I think it would totally impossible to get good results using that method. LVT is pretty flexible. I've remodeled a rental house and personally (not a contractor) installed LVT.  It turned out pretty good, but I did need a leveling compound for part of the floor.   Our church also replaced a bunch of carpet in the hallways with LVT and the installer missed a bit of debris here and there and even tiny bits telegraph thru and you can see it.
The method you are asking about mentioned hardwoods which is a totally different ball game. With LVT, I'm sure you'd end up with a wavy, ugly mess on your hands using shingles.
Why is the OSB not &quot;level&quot;? Water damage? poor installation? You may not needs as much leveling compound as you think just to at least hit the worst parts.   Hard to know without pics and more info.