
This may never die.
Approaching the problem for another angle.
1 - 0.9r = ?
either = 0 , or = 0.000r1 (that is, an infinite string of zeros with a one at the end. Which I know makes no sense, but this is maths so never mind)
So what does happen if you divide one by zero?
either 1 / 0 = 0
or
1 / 0 = 0.0r1
My intuition is the latter. Which makes me think that 0.0r1 is a coherent concept, and that it is the difference between 0.9r and 1.
Yes, I just divided by zero on the 29th of February, 2012. WTF am I doing?