At present, my "Rock" playlist has 6,276 songs in it. I call it "Rock" for simplicity sake, but it does have the occasional instrumental (like the soundtrack to Batman Beyond) and one or two Enya. But otherwise it's a pretty good classification.
And so I've tried various ways of sorting it. Sorting my albums groups too much, and alphabetical sorting gives too many repeats of covers and such. For example I probably have four versions of "Across the Universe".
So I play it on Shuffle.
One must remember that Shuffle does not necessarily mean Random.
Now I'm sure that if it truly randomly selected songs that there is an approximately 1:6000 chance that I would get repeated artists, but there are days it seems to happen way too much. Perhaps there's an algorithm I don't know about, but it still seems odd.
And as an aside, may I just say once again how crappy the dictionary is for the Blogger spellcheck?