Dak's footwork has been a problem and if you watch any tape review by Kurt Warner, Chase Daniels, JT Sullivan, etc...they all comment on Dak's "unconventional" and erratic footwork. Before you wet yourself, not all great QBs have had conventional footwork and even some SB winning QBs like Eli Manning were routinely criticized for throwing off his backfoot.
Dak's footwork has never been good or classic and it's why he has had - so far - streaky accuracy. It's no accident that with more disciplined footwork he's seeing more consistent accuracy.