Matt,
Once you have settled on a draw weight, one that you have learned through practice and practical application, that is right for you. Being one that is not too heavy, it is commonly suggested that you practice with that weight. Shooting a lighter weight, and then making the jump to a heavier bow is not suggested.
Having said that, if you wish to shoot a lighter weight bow over the summer, and then three months before hunting season you slowly work into your hunting weight bow, I guess that works for some.
If your interest is mainly target shooting, most would suggest a lighter weight bow. If you are a hunter, shoot the hunting weight bow all of the time. Sounds like you might be better served by shooting your lighter weight.
For me, the fewer things I change, the better off I seem to be. I shoot my heavier bow most of the time, I have worked up arrow weights and spines for the my lighter bow that gives me the same feel as my heavier bow, but I switch from heavier to lighter weight bow. I guess in response to your final question it might be a good way to switch back and forth.