Mike:
This is an interesting topic which I think needs some refining.
First off - a ridge need not be a summit at all, though you can always find a parent summit for any location on a ridge. Pick almost any summit, and it will have one or more ridges leading up to it. Do these ridges have separate highpoints apart from the HP of the mountain? Generally not. Take Kelso Ridge on Torreys, Keyhole Ridge on Longs, etc. etc.
The habit of making a peak name xxx Ridge probably came from cases where there was a separate unnamed peak along a named ridge. In those cases, it seems to fit well. For example, Holy Cross Ridge originally was named for more than the high 100 summit; we peakbaggers have adapted it to our own definition.
However, I think it can be taken to an extreme. For example, calling the small prominence near Mt Meeker "Meeker Ridge" , implying it is a peak of its own, doesn't make much sense, in my opinion.
Check out
John Paul Ridge in Utah. I left this off the peak list - it is not a summit, but simply a ridge leading up to Allen Peak. To say that someone has to hike to the 'J' or something to summit JP Ridge would be a little nutty, in my opinion.
In the case of Deer Ridge - to me it is the ridge that runs from west to east over the top of Deer Mountain. So, in my opinion, neither of the sub-summits you mention is the HP of Deer Ridge. Instead, the HP of Deer Ridge is Deer Mountain!