Thanks, this is a real plan of a merchant facing hard fork uncertainty, can I ask why not accepting both Bitcoin-A and Bitcoin-B in the same amount (except you are losing confidence on crytocurrency concept as a whole)?
There are several reasons why we wouldn't accept multiple strains of crypto-currency. Here are the main ones:
* Losing confidence in the concept as a whole is the primary reason. If there can be two, why not ten? If they can come and go on a whim, then how solid can this magic internet money really be? We don't want to be playing Frogger with our money (the old arcade game where you jump from one sinking log to another).
* It's counter-intuitive, but giving the customer more payment options reduces sales. It makes your sales process more complex, requires the customer to make more decisions, and thus reduces overall conversion rate.
* All the back-end overhead to manage not one, but two, different crypo-currencies would add additional expense. The exchange rates would likely be different, we'd have to deal with twice the maintenance and technical upkeep, our accounting would be more complicated, we'd lose economies of scale if we need to convert currencies, etc. Do we pay our employees in Bitcoin-A or Bitcoin-B? If some want A and others want B, but we have different amounts of each, then what? All the extra support that goes into accepting the current Bitcoin is enough of a cost given its extremely low volume as it is.
All concerns are well-thought, I am persuaded. But I think I didn't point out clearly when I say pay same amount using both chains, what I mean here is that you do not know which chain will ultimately win, so you ask your client to pay you in both chain at the same time. ( Since except for newest mined blocks, people have the same bitcoin in both chain, so they are not paying twice, they are just paying same amount in "alternate universe", when things settles and one chain wins, you and client are settled with exactly same transaction. )