>
> Why would there be an iteration count? The payer would handle that,
> wouldn't they?
>

I'm thinking about a use case I hope will become common next year -
pastebin style hosting sites for payment requests. Like, if I as a regular
end user wish to use the payment protocol, I could just upload a (possibly
signed) payment request to:

payr.com/a62gahZ

or whatever, and then payr.com can take care of incrementing the iteration
count on each download of my file. That's why it's useful for it to be
unsigned.


> If the use case is:  I give the Foundation a "here's where to pay my
> salary" PaymentRequest, maybe with several Outputs each having a different
> xpubkey, then it seems to me the Foundation's wallet software should take
> care of iterating.
>

Absolutely. The two use cases can both be supported. You could give
iteration ranges, for instance, if you want to specify expiry in terms of
number of payments rather than time.