Guild Wars 2

Hi

When a, for example, guardian gives regen for lets say: 5 seconds and it gives 1000 health and i give (as an elementalist) at the same time regen for 5 sec but 2000 health, what will happen?
my friend will have 10 sec regen (3000 health) or just mine buff or?
and what if i give the regen first or what if te guard gives it first?

because when i am heal specced and i give strong regen (for example 6000 health in 2 sec), but the others in my group give poor regen (1000 health in 10 sec), would my regen be nerfed? (12 sec for 7000 health)

grtz

1st sec : heal 200
2nd : 200
3rd : 200
4th : 200
5th : 200
6th : ur regen kicks in, 400
7th, 8th ,9th 10th sec all heals 400

aha ok, so when i group up, the other groupmembers who have poor regen better put their regen off?