Not necessarily.

When you buy 4" lumber, you are generally buying the first board off the
log. This is the one most affected by heart/sapwood differences in moisture
while drying, and even when dry and planed, has a great degree of annual
ring curvature relative to its width. It's the curvature that makes the
difference in staying flat. If the board has little curvature across its
width either because the growth rings are vertical or horizontal, it will
stay flat. Of course, the horizontal one will still have a greater
expansion coefficient.

Wide boards are only more expensive at the retail level. Until then a BF is
a BF. Thicker stock, because of the different drying schedule, becomes more
expensive at the wholesale level.

"Tom Kohlman" wrote in message
.net...
...you may all be forgetting the most important part...at least where I
live, 9" stock is pretty expensive compared to 4" or 6" stock...not
surprising when you think about it. 4" stuff properly jointed and glued
minimizes warp and is cheaper if time is not an issue.