My thinking is that people are remembering too much about his win over Lemieux, a very short armed, limited fighter who has dreadful footwork and remembering little of his struggles with Andy Lee. Saunders barely managed a majority decision despite having a 10-7 round. On my card Andy won the fight, certainly he outboxed Sauders more rounds than not.
I think Saunders has the edge in foot and hand speed, also has a better jab, so I think he could land more than Jacobs and pot shot him for 12 rounds. Jacobs only chance is by KO.