Thanks for correcting me. There were actually two comments by two different users (the links above appear identical since they have been shortened, but the full URLs are unique). I should have looked more deeply into the matter before posting the assertion and links - my apologies.

You still need access to Apple hardware. From my other comment on a similar tool: "It's worth noting that you need access to a Mac you can trust to setup your Apple developer credentials on as well as iSign and then export your credentials and certificate from each time you get a new certificate. It's likely you won't be able to do this in the Apple store. While you or I may have a colleague or trusted friend we could do this with, many developers will not."