I don't even understand why this needs to be pointed out. If the precise usage of all web APIs could be inferred from the verb alone, presumably all web APIs are exactly the same. That's nonsensical. I challenge anybody to honestly claim they have consumed a 3rd party web API of material complexity without once referring to the documentation and solely relying on guessing HTTP verbs.
Once you're already reading the API documentation, I don't understand why you'd prefer "http.request('PUT', '/resource')" over "http.post('/resource/put'). Even better, you can choose a URI that makes the most sense to your domain model, e.g. '/resource/upload'. I don't understand why you'd want to have less expressive URIs AND more work. In even this simple example, the verb is unlikely to be adequate in any case - if you need to supply options or metadata the verb is even less significant as to the true meaning of the operation.
The fact is you can always embed the verb of your choice into the URI - thereby making a GET/POST/HEAD world no more or less expressive than a Verbtopia world. All that extra verbs do is cause consumers of the API to have to remember two pieces of information (VERB + URI) rather than one (URI). At least URIs can be constructed to make as much semantic sense as possible within a given domain model - VERBs, on the other hand, end up as square pegs in round holes, making them far less memorable.