Not going to happen. The debuff can only be applied when using the mount command. It does not come into play when riding one of the chocobo's you get from the Chocobo Porters, as those are untargetable by Enemies. The thing you have to realize is that this is working as intended. The Developers want you to get off your chocobo/mount and kill the mob when you get targeted by them. That was the entire reason they installed the feature to allow you to activate your mount while your companion is out.

EDIT: Kerberon, your sig is freaking me out. The Angels are still the only thing that gives me nightmares when I watch Doctor Who.