Just letting you warlocks from Lordaeron and Icecrown known that funnel is healing for 300-400 less per tick then it should so please upvote the report so we can get it fixed. Thanks.

https://www.warmane.com/bugtracker/report/30426

Proof:
1750 to 1550 compared to Blackrock.


Drops for another 160 when entering the Arena. Making it 300-400less per tick.