Torture tests: what do they mean?

[HP67]

All the Saturn models use double-precision arithmetic by modern standards (64 bits).

Personally I don't believe more digits are the answer. Heuristics that detect and handle edge cases properly and better algebra for approximate calculations would be more helpful than more digits.

Do you really want a calculator with a 64 or 128 digit display? I don't think you can win this war of precision. At some point, accuracy becomes more important than precision.