I can't think of a single person who posts here who would refer to themselves as a "master". Even on their worst days (we all have them).
As to grammer, I make plenty of mistakes myself. But when others point out that my meaning is confused or lost because of those mistakes, I thank them, and try again.
As to agreement...sometimes it is there and sometimes not. It's not that important, but nice when it happens. What I find important is that I think...and continue to refine my thoughts. For that, I need different opinions. Kind of like a chicken eating small stones to help with the digestion.