One can generate tons of power without Sine-Wave or hip twist. If one can keep knees bent and smear feet to link body from ground through legs then core and finally through the striking arm it's very powerful. his type of punch depends on the back muscles to generate a devastating strike.
The key is to be mobile enough between strikes. When the opportunity to strike comes one must be grounded immediately to launch the punch.
This comes from a self-defense perspective. In a sport setting one might not get the opportunity because opponent is bouncing around.