I kinda doubt it. Even if it did, that's what defragging is for.
Naturally, a faster HD with a bigger cache is a good thing, regardless. I gather that putting "Macintosh," "SCSI," and "high performance" in the same sentence is something of a joke though. The Apple implementation of SCSI was robust (as SCSI usually is), but never particularly speedy. Especially with old 50-pin drives.
It'll still bottleneck at the controller.
Of course, HFS+ is impressively fragmentation resistant as it is. Even with its characteristic small block sizes. Which is yet another reason to use it if you can.