The JSAPI (aka, Google Loader) was quietly orphaned several months before the AJAX APIs were deprecated. It's now been well more than 3 years since the APIs were deprecated. All this to say that you should be looking for an alternative to the JSAPI, and I doubt you can expect any real response from Google on this issue.
And even if you did get a response, the "bugs" you pointed out were intentional parts of the design of the loader. In order to maximize performance, the actual APIs that the JSAPI was intended to load were designed to be cached for very long periods of time. This had the side effect that, when an update to an API was pushed, it might be a very long time before a browser would actually discover it unless the URL changed with every update. These URL changes would then be pushed into the JSAPI. Since the JSAPI was designed as a single entrance for many APIs, and because each API was developed by a different team with its own deployment schedule, URLs were changing on a fairly regular basis. So the JSAPI was given a short cache life so that all users would be using the latest version of an API within an hour or so of a push.
jg