Okay....I found that Garmin offers phone support, and the tech person worked with me on the issue for quite some time- we connected via Base Camp, and ultimately discovered that there is no way to just selectively delete multiple waypoints....you have to go "Delete all Symbols," and that's that. Fairly brute force way of accomplishing this, but since there were only a half dozen waypoints I'm losing that I actually want to keep, and I can easily recreate them- it's fine. I'm guessing that newer GPS models would most likely have much more flexibility....regardless, it's fine; mission accomplished. And...if someone would please explain how to mark this "Solved," I'll be happy to do so.