Can spell parameters be changed by trigger?

Can spell parameters be changed by trigger?

Well I made a Critical Strike Spell for every hero in my map, and want to make the chance to do CritStrk corresponding to the changing attributes. For example when a hero's strength is increased by 1, his chance to do CrSt should also increase some.
How will you guys make that? Could it be? BTW I don't want to make 100 CrSt spells from 1% to 100%!
Thanks... though dunno if the topic is put into the right forum.

to answer the topic, no you cannot unless the spell is triggered

Well what about a passive permanent spell adding armor? I can do Critical Strike with trigger (It's already tiresome enough), but I really can't do Add Armor with that.

use the item armor bonus, set its level to like 100 or something, then you can change the units armor bonus as you like

Thanks Thunder_eye. Got it though 100 levels seem an unsupportable number ^_^