Maybe, although if I remember correctly, there shouldn't be an analog of the 400-terrain-piece issue for steel areas, the game should stop after the 32nd piece of steel.
I'm more inclined to think that maybe one or more of the steel areas were outside the level boundaries, and so removing them fixed the problem.
Next time something like this happens, I'm willing to look at the level data to try to pinpoint exactly what's causing the issue.