My interpretation in a good footballer is someone who is comfortable on the ball and who can bring people into play with good flicks, dribbles, control and passing etc
Crouch has a better touch, comfortable on the ball and maybe even better movement, he was also good at knock downs(cushioned headers). Whereas Carroll's arial ability is quite exceptional and he's strong but passing and movement wise... weak imo.
This is why I see Crouch as a better footballer.
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