is there any discussion of paying American CC with foreign (Canadian) bank accounts?
I don't know of any discussion of it on DDF, but I'm fairly certain that it's not possible, even if your Canadian account is in USD. AFAIK you gotta get a USD account at a US bank to pay a CC.
If you're really desperate maybe you can send your US credit card a USD check from a USD account at a Canadian bank, but I would not be surprised if a US bank refuses to accept checks that draw on a bank outside the US to pay your cc. They take forever to clear, and there could be other issues.
The good news is that there are easy ways for Canadians to get a US bank account. TD (USA, through TD Canada) and RBC both have options.