I will do that, it seems a waste of time getting to this stage then spoil the effort.I fear even diluting the varnish will not slow it's drying so that you can give the finish the care you want to use.
Many modern varnishes have an excess of 'driers' in their mix. It's to cater for the hobby user who sometimes expects results in one coat.
Buy a vanish from one of the more traditional finishing suppliers online, and you should be able to manipulate the finish to suit.
It seems that most paints are the same - in this case I suppose they are to allow a decorator to finish a job fast, perhaps younger people don't know what a good paint finish looks like, or perhaps it's my OCD.