Opening season, the MCBR was barely used... just a little kiss of the brakes, hardly enough to notice. The train plummeted down the next drop into the structure (back seat airtime in spades!) providing a relentless finish with very little slowdown in the lift-wrapping helix and a flying carpet that was absolutely insane.
As the trains took their toll on the track (and vice versa) the brake was used more heavily and in some seasons brought the train to a complete stop. IMHO, this not only ruined the pacing of the ride, but also took the thunder out of the entire second half.
It wasn't the mid-course brake that took the thunder out of the second half of Giant, it was the brakes at the entrance to the helix that did that. I had one ride in the first season that the helix brake slowed the train so much, that the train barely cleared the second turn over the lift. Just when it appeared the train would stop, it crawled forward and continued on. A friend that visited the park very frequently that season saw the train stopped there on the anti-rollbacks on one visit. After the re-profiling of "Curt's Curve" in 1993, I hoped the brakes would be removed, but no such luck.
While the new ride looks interesting/crazy and appears to have a much better drop (still unsure about the turn as it drops and how that will ride), a lot of what I enjoyed about Texas Giant has been removed from the new version.