I was looking at spell id 70691. You're also right, it also seems like haste has no effect as entering in that spell id into the Log Browser shows 3 second intervals between ticks, although the Rejuvenation lasts 15 seconds not the 12 seconds of a casted Rejuvenation.
Sorry guys first post for me on EJ.
Is it normal that Rejuvenation always crit?
The same seems to be for WG and LB.