[heisenbit]

string->float conversion is conversion from accounting realm to computer abstraction. If the conversion is not accurate and the results can not be converted back into accounting realm without artificial artifacts the use of such computation is problematic.

[zokier]

The conversion is accurate up to 15 digits. Round-tripping through floats should not cause artifacts if you know what you are doing and remain within that 15 digit bound all time, and I believe that same applies for all basic arithmetic operations. So the question is, what are actually the cases where floats introduce "artifacts"