Capcom Unity posted a translation of the latest Japanese Street Fighter x Tekken Dev Blog. In this installment, the Divine Speed Gem is briefly explained, and demonstrated with the previously posted video of Zangief. Check out the quote below and head over to Capcom Unity for the rest.
Zangief is moving incredibly fast here! Man…that’s terrifying.
Hmm, yeah, deeper into the rabbit hole we go. Huh? You think it’s possible to create an infinite combo because of the speed increase? To that, the answer is no! The Divine Speed Gem increases your character’s movement speed, but does not necessarily increase the speed of your normal or special attacks. Also, the effects of this Gem only last 15 seconds at most, so once it wears off your character returns to a normal speed.
Source: Capcom Unity