Reasonably interesting, they're largely making the point that for a number of recurrences floating point arithmetic converges to the wrong value, and that it do

Reasonably interesting, they're largely making the point that for a number of recurrences floating point arithmetic converges to the wrong value, and that it doesn't matter what precision you use: any finite precision representation can converge to the wrong value. They also show that differing levels of precision can change the computation in surprising ways: there's an example of a recurrence that converges correctly in float32, but incorrectly when using float64. Just to clarify (as the paper does make this distinction) when I say "correct" here I mean the mathematical sense, not the correctly rounded value from floating point arithmetic.