Toller wrote:
If you start with face jointed wood and a decent biscuit joiner, you will
wind up with a perfectly flat surface.

If you don't face joint the wood you will have some unevenness; but it will
still be better than you could do without biscuits.

Not wishful thinking at all.

I us the PC biscuit joiner. Seems to work fairly well but generic
blades don't seem to fit quite right. It has improved my edge glue ups
quite a bit. Basically all it does is keep the edges from slides as
you probably already know. You can also do this simply with nails cut
off at an angle (but then watch out when you cut the top). Also, you
can clamp the ends of the boards to keep them from sliding and just
have to align the middle. However, after the expense, in general the
biscuit joiner has worked best and easiest for alignmnet for me BUT not
all joiners are created equal. The lamello is of course the best also
the most $$$. The PC has usually gotten a good review.

MMBR