The only time the falling thing is really faster is when you're jumping off a ledge with a ladder going down that you have to go down like right near the very beginning of sector 5. If you take a full jump, you still progress to the right at the same speed, but by the time you're back even with the ground and still falling, you'll be falling faster and save about 3 or 4 frames.
Also, I discovered another slight glitch. I had done it once in my run in an earlier spot where it wasn't too useful, but recorded over it since I needed to go back and redo a spot. If you are falling and grab a ladder at the last possible pixel so you instantly go down to the next screen instead of having to climb down the ladder at all, it can mess up the enemies on the next screen. I've only found 1 useful spot for it so far...here's a quick video.
http://abharrie.misterdotnet.com/pbglitch.zip
-Cheez