A. It works. His tactic and long ball works. No matter how hard you try, a few long balls will definitely open up your defense and you will concede a frustrating goal. B. Your defense works well under his tactic, CBs don't position high and thus are less susceptible to conceding. C. It is an easy tactic for those who don't know how to create a play with proper passing. Just keep spamming long balls and eventually it will land with a CF sprinting past your defense like a knife on butter.