I have a two story Cedar shingle house. I put the shingles on in the 70's (and on later additions as well). At first I would pressure wash and apply a water seal (with garden sprayer) every five to ten years and finally said "to heck with this." Since then I've simply left them alone. The darker color that develops, as I understand it are wood cells dying which doesn’t bother me. I haven't cleaned or sealed them in probably fifteen years and I don't intend to ever do so again. The rest of the house and property – trim, windows and doors, roof, and garden are very well maintained.
This is my experience very near the coast with lots of exposure in central CA. Not sure about your weather in CT.
The pic shows new shingles that were necessary after installing a new front door. After three years, they are darkening, but no one would ever notice the difference.
