If you summon your companion (i.e. the chocobo), you can't use Mount Roullete or summon any other mount. You're stuck with the same mount you have since you started playing the game: the chocobo.

Why add more drama/dilemma when there should be none?
Why add the code to prevent players from summoning other mounts for no reason? (more work for you, less fun for us, yes?)
Why make it hard to enjoy the perks of paying more for the game? (most mounts come from CE edition and Veteran rewards)

On top of that you have the code that temporarily removes the chocobo when entering major cities, why can't it be applied for Duty Finder and Story Quest Instances? Or at the very very least not kicking us out of the DF queue when we summon the companion. It's very dumb to get kicked w/o prior warning when you have queued for 30 minutes and want to have the chocobo to help out with the hunting log or quests.