>Survey: Who (of the people who claim flat ain't needed) would turn
>down an offer by a metal-head friend to surface grind a user plane

I would.  First, if the guy's not careful, it might mess things up bad.
Second, of the many, many old planes that I've tuned up and used,
only a few have had problems because the sole wasn't flat "enough".

Of these, only a small few that I felt was worth it, have I scraped
or lapped (metal) or planed flat (wood).   I know what the problems
are of having a jointer that's really convex or concave in the middle.
But not every plane has to be perfectly flat.   And not every plane
needs to be able to take a tear out free .001" shaving through
tight mouth.

Walter
use first, lap later.