Hm...I can see the utility in it. Looks like lecturing has been getting cleaned up too. That's good, though to be perfectly honest, I think teaching probably should have it's definition tightened if we wish to keep lecturing. As it currently stands, it's a ridiculously broad tag that houses post #6756329, post #7002278, and post #6794218 in the same breath.
Perhaps, assuming we wish to keep lecturing, we could make lecturing more a tag for the more traditional definition of teaching, whereas teaching could possibly for used for everything else that falls outside that umbrella, but is still teaching, and thus, should be searchable. I imagine some people don't want to see post #6829642 looking for things like post #7094382, after all.