That guy seems to be impossible to explain this. His argument is now reduced to the assertion that Bitcoin will fail because of paperwork businesses would have to fill out for exchange rate gains. I hope somebody would come here and explain it in detail whether it actually requires that much work and how often
Personally, I don't believe him but have no experience in this field to refute with competence...
Is it so difficult to understand. You will need to record the USD/BTC rate on every transaction. Here the problem starts, which exchange rate are you using ? The Goxed or the Stamped one ? Don´t forget the timestamp of the transaction needs to be matched with the price at the point of exchange of goods. Just imagine you would do 100 transactions as a merchant a day....
What you say are the problems we already have today (and had yesterday), there is nothing new. Then how do we handle them right now and how is Bitcoin different from any other foreign currency we have to work with? These problems are technical issues only. If such a need does arise, they will be fixed pretty soon through automation and what not. Do you think that payment systems like Visa or MasterCard or whatever are less intricate inside?