Martial Arts - Is this a Bug?

I am relatively new to MxO and I seem to experience something that as far as I can tell it should not happen.

I am level 23 and I specialized in Martial Arts, I have all the MA abilities I can have at my level coded and leveled but so, with the memory slots I have I can have up to 2 Martial Arts in the Master tree.

Now, the theory is that if I have 2 loaded they should stack but it's not happening, actually, the overall statistics seem to be the same regardless of the combination (i.e. Karate/Aikido, Karate/Kung Fu, etc).

Also, no matter what is the Max HP% depending on the MA type, I never get an increase in my Max HP.

Am I missing something?  Thank you for your help.

Shayel

PS: I look at the summary page with the combat abilities and the upgrade one and that is here I noticed that the abilities seem not to be influenced by the MA combination at all.