I am kind of surprised I haven't heard anyone mention this before. I have noticed that pets usually have less health than their masters, and while in some cases talents might caused it, I doubt every single hunter I encountered wasn't BM.
I played on Feenix for years, and back there, pets usually had more hp than their owners. The only situations where I saw a hunter have more hp than his pet was some very well geared hunter.
Is this the way it was on retail? Is it possible that pets on Feenix were bugged and had much more hp than they should have?