@dc42 Hi, yes It is true. In the mean time I noted this by myself and I have adjusted the single probe by G30 with the right value of x and y shift to have the same point to the 0,0 point probed from the mesh probing. (in my case 0,-29)
I have also adjusted better in the same way the 4 bed leveling points to be similar at the 4 corners of the bed mesh.
I can say now that works as expected.
It was very very very tricky:
when I was ignoring the x,y probe offset (applied from default on the mesh, but not on the single first G30 probe) the point of the first probing fell between the 0,0 point and the 0,70 point on mesh that have a strong deviation with different sign too: +0.042 and -0.046.
(wtf of luck)
...and the 4 corners at about 0.002mm!!!!(so in the real far away from the real 0,0 point about -0.003mm)
(wtf of luck)
So you can understand, I saw "something" same a mesh "grounded" on the 4 corners!
When I had put the first g30 at the front left corner, similar at the first point probe from the mesh (always ignoring the shift) I saw a mesh shifted down, but also in this time not with the first point at zero as expected!
...than the repeatability error of the probing does the rest.
So such a mess in my brain.
