What the others have said is absolutely correct, however if you like cruise than by all means use it. I generally use cruise on long interstate trips while listening to an audio book to relieve the boredom. Generally drive faster then normal, to save time.

That said, I never use cruise on my daily commute. The commute is short enough that fatigue is not an issue. If there is traffic or if I'm in a hurry I'll do "traffic friendly" (high speed) hypermiling. When there is no traffic and I'm not in a hurry I'll switch to full blown hypermiling, which may include coasting segments where speed dips pretty low. It is not something you should do in traffic IMHO.

Full hypermiling uses the least gas, cruise uses the most, and "traffic friendly" hypermiling is a compromise. I do all 3 depending on the situation. LA to SanFran is a long enough drive I'd more than likely use cruise.

Don't feel bad if you like to use cruise. If the drive is fairly flat hypermiling wouldn't help much anyways. You can save gas with cruise by slowing down at the expense of adding more time to your trip.