LibMotoSh was a famous extension back in the 1990s. It boosted PCI Power Macs' FPU performance - but many said it did so only on benchmarks and in real-world use it actually harmed performance. Your experience seems to confirm that.

It makes sense in a way that it came on your Sonnet CPU upgrade disc, because it was precisely around '97/98, when G3 upgrades for the PCI Power Macs became popular, that LibMotoSh gained prominence as a benchmark booster.

M