Certainly all planes don't need flattening. As far as lapping, that is a skill that will ultimately make a better user than some surface grinding. The criticism on the states forums seem to come from machinists who flatten planes but who don't do woodworking, though I have seen examples where someone overdid hand lapping and the subject plane was left behind with a very proud toe and heel - like several hundredths.
What's most desirable is a plane that troughs at the mouth and is slightly proud of a surface (like a couple of thousandths) at each end. That's not hard to do, it's easier, in fact, but maybe suggesting to beginners that it's something they should do is a reach.
I received a norris this past week, a later panel plane. It appears to me that someone had it lightly surface ground, which is puzzling. I suspect that because it has mill marks on it, no wear or even scratching on the metal, but obvious hand wear on the wood. It was very flat from a specification standpoint, but the toes are slightly lower than the mouth (like by a couple of thousandths). That is a pain on something that is to create a flat surface, because it has to nip a few shavings off of the ends of a board before you get full length shavings. I lapped it to the condition I mentioned above, and now it works more nicely.
Sort of getting off point.
I agree on the waterstones. I think they are subpar behind older methods for anyone doing more than dragging a plane iron backwards in a guide.
