Guzan, 28, claims Dempsey's ability to combine graft with craft would have made him the perfect fit for a Villa shirt in Paul Lambert's new regime.
He said: "Clint's a good guy for sure and it will be exciting to come face-to-face with him at White Hart Lane.
"He's certainly had an eventful summer! But his commitment on the field is second to none and he puts in a shift every time he steps on to the field. He brings goals to any team, he's a scrapper and a fighter and he's always going to give you a hard time.
"He's just a fantastic player who will help any team he steps out for. Clint's always in the right position to score goals and set up opportunities for his team-mates.
"He's the best of all at that and would have been ideal here at Villa. I saw him during the last international break and we chatted about it. We had a laugh, now the plan is to show him he picked the wrong club the day he signed for Spurs!"