Traiting “Warrior’s Sprint” makes “Bull’s Charge” remove Immobilize on activation as advertised, but the character doesn’t move during the charge animation if the trait in question triggers, which makes this skill completely unreliable for this purpose. Every other utility skill affected by “Warrior’s Sprint” (such as “Kick”) behaves correctly.
I apologize in advance in case this has already been reported—the search function didn’t return any comparable results when I used it.