Okay, I’m watching a DVD and reading the pattern. It says:
Knit across with Color A.
With Color B, K1, Sl 1 WYIB, K3 to last st, K1
With Color B, K1, Sl 1 WYIF, K3 to last st, K1
I keep ending up with one less stitch at the end.
Also, when I slip 1, then go to knit the next stitch, the working yarn is always one space back on the needle, as though I have to go over the slip stitch.
Your working yarn will be one back, because you don’t work the slipped st. So you go from previously k st, over the sl st, to the one you will knit. Is that what’s happening? Well, it will do that when you sl WYIB at any rate. Not sure WYIF though