Mike Dodd wrote:

Then a third, easier suggestion, which doesn't sound right to me, but if
others have had successful experience of this, then it's a good option.

Sorry for presenting too much info.

Don't apologise to the Beale arsewipe. He's a known troll from other
newsgroups and can't tell arse from elbow.

I'm not a great fan of glued block worktops. I have used them and I have
made them in the past. But they're a lot of fiddling about to come up
with something that (IMO) doesn't look that good and doesn't work well
either. In general they're cheaper to buy than to make, Ikea offer
suitable tops at a reasonable price. They're useless for the purpose
that Ikea sell them for - kitchen worktops - because the glue they use
isn't fully waterproof, but they do make decent (ish) desktops.

If making them yourself then IMO it's fairly academic whether you join
them by simply glueing PSE, biscuit jointed, dowelled, or joined with a
fillet or T&G as you suggest or think the bloke at the yard suggested.

It's possible to buy cutters for spindle moulders to create the tongue
and groove or to machine a comb edge to increase the glued surface, a
small spindle moulder will cost about £100.

A good quality oak worktop 3m x 950mm x 38mm will cost you about £250.