[jcranmer]

To get the right answers for accounting, all you have to do is pay attention to how you're doing rounding, which is no harder for floating-point than it is for fixed-point. Actually, it might be slightly easier for floating-point, since you're probably not as likely to skip over the part of the contract that tells you what the rounding rules you have to follow are.

[munch117]

Agreed. To do accounting, you need to employ some kind of discipline to ensure that you get rounding right. So many people erroneously believe that such a discipline has to be based on fixed point or decimal floating point numbers. But binary floating point can work just fine.