I agree that NUM 3.2.x was excellent (and still is) for what it can do with 030-processor Macs, and 040 Macs running no higher than 7.6.1. Received wisdom at one time was that NUM never leapt over the chasm to HFS+. Whether that is/was the cause or not, it was many times reported that its use with HFS+ format was, to put it mildly, fraught.

DiskWarrior will deal with System 7 HDD directory fragmentation, but it does not boot (or, at least, v2.1.1 does not) less than OS 7.6.1, and its companion file defragmenter PlusOptimizer demands a PPC processor. Norton's SpeedDisk (not always so speedy at 16MHz with 1GB drives and up) is an excellent file defragmenter for older Macs.

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