Do Jolteons dodge better than Vaporeon, Snorlax, etc. when defending gyms?

I've noticed that Jolteon's agility can make up for their lower HP. Rather than go toe-to-toe with a Snorlax, Vaporeon, Slobrow, etc. and make it a blow for blow bloodbath, Jolteons can compete because they are best at dodging. The Jolteon can "float like a butterfly and sting like a bee."

That said, to bring diversity to a gym defense which is often a high HP based on water defense, I like leaving Jolteons. But, there is such high turn-over at gyms, I can't tell (yet) if diversifying defense with Jolteons adds value. Maybe I should ignore diversity and just leave the highest HP guy I have.

The only way it makes sense to leave Jolteons for defense is if Niantic exploits their ability to dodge. Does anyone have experience or knowledge of this? I bet few have ever even had to face a Jolteon in a gym.