> As for fixing your present bench.

I'd call the present bench a total loss.  No use carving on rotten wood,
as Confucius actually did say.

> adding a surface of plywood would be a really good thing - benches that
do real work are often made with ply, it’s a good surface, it’s 
‘disposable’
so adding nailed stops or screwed on jigs is OK.

Good point, though I use 3/4 inch termite barf on the top of my big 
bench
(4 ft by 8 ft).  When it gets funky, I flip it over to the fresh side 
for
another few years.  It's gone through two sheets since 1985, now 
starting
on the third sheet.  With termite barf a slip of the chisel doesn't 
throw
up splinters, and with its smooth surface you can draw lay-outs for a
project.

Mike in Sacto