That was my suggestion, sorry, I have been away.
The way you described is different, you left the first stitch knitted on right needle without doing anything to it, ignored it, and started binding off all the other stitches - rather than after dropping it off the second knit stitch but threading the last end of a needle through it.
Never mind, you just started the cast-off round one stitch later! When you
are up to the last stitch, find the first stitch you cast off, put it on the end of the needle, and cast off that stitch that used to be the last.
The jog here is, I think, not because of the spiral, but because the cast-off edge is not joined. This technique joins the ends of the edge well and consistently.
If you find a way to improve on it, please post.