Guild Wars 2

I understand that when boons such as Regen “stack” its potency does not change, only its duration. My question is what if player X who has no Healing power casts a Regen and then before it runs out player Y who has lots of Healing power casts a Regen of his own, does that mean the weaker Regen remains weak only with a longer duration?

I hope i explained myself.

This is explained in the wiki here: http://wiki.guildwars2.com/wiki/Effect_stacking