did you test this?
i made several tests and animal bond glyph works with spirit bond(Will test it again today to clarify this). (its still just *500 hp heal more depending on your max hp so no big deal)
Also since you just use it as bm ( mm no pet =D) it is tons of times better than Iron hawk.
Just take the talent, do a fight. On the one hand you have the Amount of the Reduced Dmg which is 1/10 of all dmg gained and on the other hand you have selfhealing done by spirit bond. check the following formular
Healing by Spirit Bond - (Dmg gained /10) you still will have a positive Value. ---> Spiritbond > ironhawk
For example checkout this log
Dmg taken:
https://www.warcraftlogs.com/reports...e=45&by=target
Dmg gained 2.74million during the fight -> 2740000 - 265k absorb = 2.48m /10 -> 248k dmg reduced due to ironhawk
Now lets check Healing done by spirit bond from the same fight
https://www.warcraftlogs.com/reports...ling&source=45
469k Healing by Spirit bond - 248k dmg reduction by ironhawk = ~220k damage negation more than ironhawk and less heal power required from healers