Have put some gloss Dulux polyurathane on a table top, but the end result is
just far too glossy and it just shows up every brushing blemish. Is there
any way I can add something to it to make it produce a matt finish (other
than rubbing it down after its painted on) ?

Failing that does anyone have experience of which is the best 'matt'
polyurathane clear varnish out of Dulux, Rustins or Ronseal? Thanks for
advice.