Err, is it just me or is the Duration: Event from the Defixio Magic chapter of AnM the same as the Duration: If (Condition) from HoH:MC Merinitia chapter except that the former is only +1 magnitude, whereas the latter is +4 magnitudes?
BTW - the Defixio Magic chapter is a good one so kudos to John Post for that. It draws heavily on the Athlone Press Witchcraft & Magic in Europe series which I appreciated immensely for those interested in reading further.
The Spell Timing r/d/t's, in general, are extremely versatile. So yeah. Spell Timing will probably overlap things. It's hardly a problem that Event is more efficient, though -- if someone wants to put the research time into doing that, they've earned it.
Very close but not entirely. The 'If (Condition)' is limited to one year, or if the caster dies, but on the other hand the Ritual versions might trigger multiple times. But other than that they seem quite similar.