It's a fault when a flushing dog hesitates at the flush. I had an Irish Setter when I was a kid that was a pretty good coon dog. Doesn't mean that I'd like to see Setters bred to be coonhounds. Aggressive flushing is a trait to be bred for in labs, in a pointing breed, not so much. Therein lies the problem with registering "pointing" labs with the real deal.
