Linda:
It's perplexing, to say the least. If I open a book - I mean the old-fashioned printed-on-paper kind - I wouldn't think of starting at chapter 7, then moving to 4 then 6 etc. However, in my own stats I noticed that one reader had read an entire 7-parter of mine, in the order 3, 5, 1, 7, 4, 2, 6!
I agree and it has puzzled me. Being a slow thinker I like time for my story line to develop and reading parts 7 and 6 before 3 and 2 (and in something of that order as my stats have shown!) I'm sure is robbing the reader of essential value. The reading technique I adopt is to look at some of the comments first and if all seems to my taste and interest then I'll start at Part 1 and if all is well carry on from there. If it is a particularly long serial, I might just delve into a middle section to try for the feel of it, then if seeming good it's straight back to Part 1 and on with the show.
Perhaps we should take a tip from the old cinema if, as I believe, some readers look simply for a juicy piece of spanking, and grade the serials by degrees of violence. Remember the old 'U' 'A' and 'X' certification?
How about three levels of severity: considerate/playful, punishment/severe, brutal/judicial.
Then there is the pace: slow/psychological, spanking trot, hot gallop.
Yeah I know, pity the poor validator but I think there is a genuine problem here which I for one find quite galling.