Please name one other DPS that would not do the same with guard and heals? That is not a AP only feat. Additionally, guard and heals do not make your damage greater, just your survivability. So in essence you are backing up his argument that AP are glass cannons as they need said Guard and Heals to negate that weakness.
I happen to main AP as well, and without heals or guard, I can do a lot of damage yes, but I die very easily. I find the trade off fair. I also do more damage on my sniper than my AP and I have more survivability. This is of course solo queued, in group make ups things can change, not damage though, just survivability.
I do find it amusing that people who call others 'child' or 'kid' on forums are so often the ones that make mistakes in what they say and show, dare I say it, their age .