Processing Mechanic Timing

Beepbeep

When you have a gear set that proc's and it states "...ability lasts for X seconds; and "This effect can only occur once every Y seconds." Does the timing of "Y seconds" start when the proc initiates or completes?

or basically, can it process again after X+Y or Y-X seconds?

Anyone know? or does it depend on the actual set?

UppGRAYxDD

If its a magicka set, It will take double time to proc again....If a stam proc set, it will fire every 2 seconds on both bars