Asking for experiences should not be off-topic.
Sharing practical experience is (to me at least) one of the most important forms of help a teacher could get from a colleague.
Such questions do not have a definite answer but I would like to see them here, so I would propose making them community wiki — as far as I understand, that is what CW is meant for.
(This proposition was a misunderstanding stemming from the usage of CW on MO. After reading quid's comment below, I see no reason to make discussions CW.)
I think some forms of discussions are ok here, but they should be focused and about mathematics education.
I think the question in question is sufficiently focused and could provide useful material for future readers.
Making useful and findable material should be an important goal, not only satisfying the needs of the OP.
From a different point of view (also mentioned by quid), I think we shouldn't be too trigger-happy when rejecting off-topic questions.
I think we still need to experiment what works and what doesn't.
We are not getting too many new questions at the moment, so I would welcome almost any kind of questions about teaching and learning mathematics if their potential answers could be useful for future readers.