Everything you describe is a difference in precision, not accuracy.Kind of a funny way to bring a 6-year-old thread back from the dead, because dive computers are both more accurate than dive tables, and they are more precise than diver tables. Accuracy and precision - Wikipedia

They measure your depth in typical increments of 0.1ft/0.1m versus of 10ft/3m for tables, and typical increments of time of 1-5 seconds instead of 60 seconds for tables. Dive watches make measurements of similar precision, of course, but the tables themselves are about an order of magnitude less precise than computers.

And for multi-level dive profiles (that is, anything besides a perfect square), they will also measure your depth over time more accurately. Even for square profiles, the accuracy captured by the dive computer is a little better as well, due to their improved precision.

measurement in smaller increments is a difference in precision, not accuracy.

Both the tables and computers represent algorithms that fall in the category of numerical methods, where the differences all deal with data resolution, i.e. precision.