...And since we had ID'ed (actually multiple times) within the last 10 minutes (on the same frequency, BTW), therein lies the gray area.
Actually, whether or not you had IDed on the frequency beforehand doesn't matter. The
question is, did you ID within 10 minutes
afterwards, in the course of making further
contacts on
that frequency.
If you tuned and didn't say anything further for 9 1/2 minutes before IDing, then I'd say you
should have IDed, because that was reasonably the end of the transmission. But if you called
CQ a couple minutes afterwards, that is sufficient ID for the tuning transmission.
At the people level, there are two issues: one is recognizing whether or not it is a rule
violation, and the second is how much of a deal to make about it. Both are important
for newcomers to learn and understand. We all make mistakes occasionally - forget to
ID in time (or the rig blows a fuse before we ID), or accidentally transmit with the VFO in
the wrong band segment, or whatever. Yes, that's against the rules. No, you won't
loose your license over an accident like that. The point is to recognize it and learn
to be more careful next time. The point is not to do it intentionally, and to minimize
the accidents. FCC enforcement is limited to those who intentionally flaunt the rules.