No, in my suggestion we'd always use the cached file, unless the remote file had changed.
Yes, yes. I understood that.
I ask again: What does "you could use a way out of date file without knowing" have to do with anything? If you ping the server and don't get a response, you use the cached file, just as if the remote file had not changed - since you have no way of knowing if the remote file had changed.
What else could you do?
Unless you thought, for some reason, that we'd not ping the remote file if there was a cached file - which is not something that _I_ have ever suggested in this thread. In fact, if you look at MY words, you will see that I said:
Not a bad idea: refactor the config loading a little to iterate over a sequence of URLs, culminating in a locally cached disk file, and give up only if all of those fail. Upon successfully loading a .xml file, save a local copy. Doesn't seem too hard.
You want to ping the modification date, rather than loading the file. A nice optimization - for a file that we will load exactly once per session, at most, unlike images, which can be loaded hundreds of times per session. And, therefore, it might just be over-engineering things.