No, not lagging, she is right next to me loose lead (and i use a mixing spoon with yumz on it as her target) and when i stop I lift the spoon up straight, slow, and slightly rearwards while saying "sitz". She does the motion to sit all the while albeit backing up too far. Instead of her butt going down like her normal sit, she takes steps back and sits.
And yes, I wasn't expecting perfection in three days. I'd have better luck winning the lottery.
Mhmm! We do play/train/play sessions - and you are correct, she is SO eager to give what I request. I continue to correct her sit/down command but the sitting as we stop has me perplexed...