We had our gutter cleaning season cut about 3 weeks short due to a cold December. We tried about everything over the years from rubber mallets, metal hand shovels, and an electric heat gun. While a lot of time you can throw enough tools at a job to get it done, it kills your efficiency when things are frozen. We found we were just not able to make an acceptable hourly rate working on frozen gutters.
The idea of a steamer is great, but by the time you factor in the additional setup, operation, and pack up time on top of your gutter cleaning time, it does not seem worth it just for gutter cleaning. It would be a different story if you are also removing ice dams.
I would love to hear if anyone else has been able clean frozen gutters efficiently.