what you did wasn't that -- but I would just like to point out that simple concise explanations helps the community as a whole; it's not just the ignorant that lose out.
Yes, I know it's likely not your job to educate, and maybe it's a bother that someone acts expert on something that they're clearly not -- but those that care to educate serve everyone in the context of an online forum, not just the naive or ignorant.
I'm no GPS expert, I've read some of the theory had enough of a working understanding to deal with tactical navigation systems, but that was in my past. I remember using El-Rabbany's "Introduction to GPS" text.