I agree with maxg. The boom kick ball tends to occur depending on the skill level of the players in the national at the time. The 74 team in Haiti played a mix of long ball and short passes throughout the qualifying, and almost succeeded. And that team had speed and we beat Mex. The Italy WC team was not total long ball with Gally as coach. He had some skillfull guys on his team. The Germany WC team did use lots of long ball, but that is what the the Dutch decided to have them play.
Now the U-20 had to use the long ball quite often the other night because of the heavy ground, and Mexico was fitter, faster and better than them.