At 10 counters if you are hitting a lot in AOC and depending on where your NW counter, it was at already though NW should give about that of the blue ring burst, you can get it to proc twice in the amount of time. You would be waiting for the blue ring to cool down, so that is two burst components from NW in the time; you would only get one from blood flow.
You could wait till you have 10 NW counters in game (aoc gold)and wait for blood flow to wear off as we said it's situational, then the NW heal and the up front portion from blood flow stack of course. If 750+ at 10 counters of NW are accurate, if we will have to check the numbers on the NW, then that's twice what you get from the bloodflow bulk portion.
Of course this can be co-ordinated so it happens on purpose, but in raids where most people do not understand how healing works. We are still trying to get people to understand why 3 healers in one group is a waste, it can be beneficial. Not to mention that the bear shaman blood flow can be specd to give 6.5% more healing, refreshing it may over-write a lessor HoT for that fraction more healing on the target. We provide age of conan gold for you here.