We value everything you do here, but please be a bit more judicial about replying to terrible posts. When they just can't comprehend patch notes such as this it doesn't help to feed them. Thanks.
Originally Posted by Nymueh
First of all, this thread is my 'go to' for theory and practical application, and I thank you for the cogent and comprehensive information. Having said that, I'd like to note that as of 4.1 happiness is no longer a pet attribute. With that change, the Mend Pet glyph has transmogrified to Glyph of Lesser Proportion which merely makes your pet smaller. This seemingly insignificant alteration has a bit of a ripple effect, requiring the carrying of pet appropriate food once again, rather than spamming an occasional 'mend pet'.
I've substituted Glyph of Aspect of the Pack for the transmogrified Mend Pet=Lesser Proportions. It has been quite handy in the new heroics.
I made the same glyph change.
However, you should not be required to carry pet appropriate food. All that food does is heal your pet out of combat. You can do that just as easily with Mend Pet. The food is just useful when you want a quick pet heal during brief combat breaks and do not want to have to rely on the healer to use mana to do it.