Cap America knows pressure points to that's not the difference. Cap should be faster than him since he see's bullets in slow motion, and has crossed a room to block a bullet after it was fired speed blitzed rooms of people etc. Tai isn't too far behind, casually blocking high velocity ballistae shafts, running up falling debris, cleaning a prison full of enemies in roughly a minute blah blah blah
Tai Lung wins this through have greater skill IMO, and a better damage soak than Cap.
Tai lung is stronger and is also the better fighter, he defeated the five furious with ease, who would, in my opinion, stomp Captain themselves( they're too fast for Captain). The shield is a non factor here.