It will also tell a lot about the capabilities of the US and Turkey to support their anti-Assad allies. Notice that ISIS is not the primary target for the Russians and Iranians.
You're absolutely right. Aleppo is not an ISIS stronghold, but is a strategically important city to Assad. The Ruskies and the Iranians are going to test and see how much of a stomach Prince Barry of Sodom has for a real fight. My guess: not much. He'll cut and run and abandon his Sunni "moderate" allies. In two weeks or so, the Pentagon will announce the end of the Syrian "training" mission, and Prince Barry's humiliation will be complete.
“Notice that ISIS is not the primary target for the Russians and Iranians.”
Actually, those anti-Syrian forces are ISIS. They are the front group who are the prime recipients of American hardware.