I use a Thermowell now and I have it set at a 1 degree differential - probably not thee best for my compressor. But honestly it doesn’t seem to come on any more than before.
But for years I just set the ambient temp at about 4-6 degrees below my intended fermentation temp and watched the little stick on “Fermometer” and simply adjusted the temp that way. I never saw a variation on the temp strip due to the 6 degree differential of my old analog Johnson controller. It was an easy way to accurately control fermentation temps and it is a method I would feel comfortable recommending to anyone.
BTW I was pretty sure there wouldn’t be too much debate on the subject. LOL! 
