After playing with 0" Overlap for the last month, my conclusion is that it doesn’t miss any more grass that using 4". Yes, both still have misses that shouldn’t happen, but reducing the overlap doesn’t seem to increase them.
This doesn’t make obvious sense but in my experience it’s reality. 0" overlap saves 20% on mowing time with no negatives. Of course, as property sensitive as Yarbo seems to be, your results may vary. Give it a try, worst case, you mow again… from your chair.
I always do 4" overlap, but tried 0 for the first time on two areas. I did not like it, it left about 1/2" stripe uncut on every line. So it was worse for me. This is a pro mower, the M1 could be different.
Understood. Thanks for the input. It works for me but may not work for others.
If the trimmer was installed, I think it has an impact.
But why???
It changes the turning algorithm some or ultimately because when the core is backing up or pulling forward and it trips one of the limit switches, it has to adjust its maneuvers to deal with it and I’d hazard a guess this is why it is allowed to deviate from the path line considerably more than it used to be allowed. Because it just ignores the fact that it is well off course and continues on instead of reversing to catch all the missed grass, you end up with strips of uncut grass as a result. Unfortunately, I see this too on slopes or tight corners without the trimmer.
No trimmer, I never cut with the trimmer.
0inches works for me in my field with 0 trees zero nothing, super flat (about 1 acre). For the rest, 10cm is the way to go, else there are uncut strips.
I guess I should’ve qualified my suggestion. I do still run 4" overlap in smaller congested areas with short turn-arounds. Big areas work great.
Sorry to get everyone all excited 
I’ve been using zero overlap for about two months and could not be happier with the results. The lines are full width and very uniform. I’ve not experienced any missed areas and during summer mow three time per week.
I switch between 0 and 4inch depending on rain forecast. 4 misses less for me. I think it’s because the mower lays down the tall fescue then brushes it up on reverse overlap path on the overlap.
Because of the wet Summer for us, I’ve moved the cut down to 3.4 which also helps at 0 overlap which minimizes the lay down. I’ll have to go back to 3.9 when we get into drier months to keep from burning the smaller grass blades.
But since I only have 1/2 acre of grass, there are more turns, which is another problem in itself.
So why are we restricted to 0", 4", and 8" (aka 0cm, 10mm, 20cm)? I also use 0" for the speed benefit, but wish I could choose 1" or 2" (aka 2.5cm or 5cm).
I am not asking for User Definable distances, rather add 2" (5cm) to the allowable overlaps choices.
You’re welcome to create a topic for this in the Suggestions and Feature Requests category. I’ll keep an eye on the discussion and see if more users share the same interest in this idea.