When a red uses the DF in jailbreak, the cooldown between shots is over 5 seconds making it unusable. My guess is that this is a bug due to the increased cooldowns of rechargeable items such as the gas passer or jet pack also affecting the weapon. It could be possible that this is intentional but I believe it is probably just an unintended side effect. I'd love it if it was fixed as its personally my favourite primary for pyro.