Bill,
It depends on what your seeing. There is such a thing called drgon skin. I which you see the pattern of the weave, but the weave is fully filled. Many of us me included sort of like the look of drgon skin. It looks cool and it means your weave is soaked to jsut the right amount

If you are seeing dragon skin don't add to it with a third coat you are just adding weight, unless your eally want a flat glossy surface.

If however you ar seeing fabrick that is lifted up or starve. Starved fabric looks whitish. Then you may want to sand down and reglass that area.

Don't us the varnish to fill the weave.

If you have th capacity to post a picture it might help us diagnose which of the two possibilites this is. If not I hope the words give you enough info to diagnose it for yourself.

Good luck!

!RUSS