That’s true, but I think it would make a very unique character. A lot of people have complained that a lot of the current Instincts simply allow a character’s special meter or ability to always be “turned on,” or simply give frame advantages, and I think this would make a nice change of pace. Maybe the Beast plays completely different and simpler, a rushdown type character, while the Master plays more like a zoner, or defensive fighter.
I’m just throwing this out there as I think of it, to be honest. But I feel like we have characters who only reach their potential when you really train with them (Maya, Kan-Ra, etc) so requiring a lot of practice as the Beast doesn’t seem too out of place to me.