In regards to violating HTTP, Frictionless Sharing isn't in any way different from every other non-RESTful service/site on the internet. Facebook could have jus

In regards to violating HTTP, Frictionless Sharing isn't in any way different from every other non-RESTful service/site on the internet. Facebook could have just as easily implemented the same service RESTfully (not violating HTTP), and it wouldn't be any different. GET requests have the stateless/idempotence constraint so that they're cacheable, and timing between requests, out-of-order requests, and multiple requests don't become an issue. The 'accountability' referred to in the post is about users of the API - they shouldn't be expected to be aware of server state/side effects, in the same way that users of a function call shouldn't be expected to be aware of its implementation/side effects. It's an engineering constraint - it's not about honorably keeping end-users unaccountable for reading your webpage.