if its anything like the crusader enchant, (and that seems like a likely guess) then yes, its based on a PPM formula. however, its still a good enchant, and there were many times back at 60 that my dual 'sader enchanted weapons would both proc on me at or near the same time, giving me buttloads of extra str and a nice little heal.
only way to know for sure is to try it out yourself. find some green 1h's, enchant them with fallen crusader, and then go hit the training dummies up in town (or duel a high-armor target who can heal themselves like a pally) and see if both can proc at once, and what the proc rate is like.