I called Interlux (they make West Marines varnish) and was told that it would be a problem - maybe. They told me how to remove it (Inter-Strip or sanding) but were really vague otherwise "it may or may not be a problem"

I think I'll wait a couple of days and do a bit of scraping on it to see if it feels right. I hate to remove it unless I really need to. Of course, I could just keep right on coating and worry about it IF it fails.