Alright, I think this is good to wrap up …
Host states they run ruid2 (dso in a suexec environment), following the trend of hosting providers that standardize on current PHP builds (5.3.28 for my account), “… due to its concurrent, multi-threading and security which combines the natures of security of suphp with the speed of fastcgi and is being recommended by cPanel as well.”
Everything covered here, your input and their’s, all sounds good and focused on one sort of best practice of another, so I’m not going to split hairs about it. I can see that both of you are working to keep up as best as can be given the multitude of ever-changing requirements of your businesses, technology trends and standards, professional opinions and pesky, persistent customers! 
Which is to say, kudos to you and your team for helping me get to a point where there was enough valid information exchanged to get my Host to make a well-informed exception on my account and disable mod_security (which apparently only they can control, not me via .htaccess instructions) … the AutoMagic button now works as expected: no more 403! … Yeah!
If there’s anything further, I’m all ears … otherwise, thank you very much again, and have great day!
Bob