Mysterious Dialer battery usage

If you’re using an HTC Android (with HTC Sense, although I’m pretty sure they all have Sense) phone running Gingerbread (2.3.x), you may have noticed that the “Dialer” process seems to be inexplicably showing up at or near the top of your battery usage list. After seeing various people allude to the fact that the battery usage seems to be caused by sensors usage, I finally figured out what was causing it: In Settings -> Sound there is an option for “Pocket mode: Increase ring volume while in pocket or bag”. Having this active seems to keep the sensors in use all the time, presumably trying to determine whether the phone has been placed in your pocket / bag or not. After disabling this and rebooting (not sure why the reboot was required, but it seemed to make no difference before I rebooted), Dialer is now mostly gone from the battery usage list. Overall battery consumption doesn’t seem to be affected too much, but since I didn’t really find that feature to be very useful in the first place, I’ll probably just leave it off. In case it matters, my phone is the HTC Desire HD, but I suspect this will affect other Sense / Gingerbread phones in exactly the same way.

EDIT: Okay, this may be a red herring, and it’s just that the reboot fixes the problem; after receiving a phone call, the “problem” seems to be back. Apparently the latest HTC ROM base may fix the problem, but I haven’t had a chance to try it out yet.