Here's a quote directly from the company's web site that may answer your question:
"If one of your devices is not recognized
by the Harmony wizard, the web wizard will learn about your device and will automatically add it to its database."

In other words, not only will your remote be capable of "learning" your projector's codes, but you could be updating the database for other users of this device.

I have been researching remotes for the past week and, so far, this remote matches my requirements better than any other.