KC
Great test, yes you are correct. I just say if you put the gun down for any period of time to just double bead the first 6 inches and you will be fine. In the summer you might not even notice the off ratio mixing. A great test to see if your system is performing correctly is to take a popsicle stick and rub it over your seams or laminated edges, if you have some areas curing slower/faster than others (1-3 minutes slower/faster) something needs to be corrected.
Ray