I have now been knitting for the princely sum of Two years! I can hardly believe it, I've knitted so few things for actual people :-P
I started off with a real thing for DK and to be honest I still can't resist it, but one thing I've noticed is that DK is all different sizes!!! And indeed I have some 4plys that are more like DK. This of course adds an extra bit of excitement when trying to see if a pattern will work and ensures that your knitted item will not turn out as planned. I've knit the lati dress in all different DK's and they have all turned out differently, not always in a good way.
Double Knit can sometimes be called 8ply (8 stitches per inch) and appears to be a UK term. I don't see why we can't have all the weights of yarns in the UK so we can do US patterns without getting confused (or is that just me?) If anyone can give me a clear definition of DK I would be grateful!