Basil was definitely a zone man and challenging the shooting pocket person. The point I have tried to make over an over (and I do believe you can do things in highschool that you can't in college) is that whatever you call your defense, it is always a combination of court position, ball position and player position with all of those a function of who has the ball and where the others are. You can take a zone and make it almost the same as man and you can take a man and make it almost a pure zone. in the most basic sense you are wanting to defend a makeable shot, whether inside or out and have good rebounding position. Your choice of D may or may not gamble for steals, but will rarely play all people as equal threats. I think Basil tried to see if possible every team he played 5-10 times if possible...and that many times gives a much better feel for the team when playing them. Knowing the players tendencies and accurately understanding your players abilities is key as you suggest. FWIW, I have stated many times that you can take anything and if executing it to a high degree be successful. I think too many on here don't grasp how close defenses are. I can take man and adapt to each player. You can take zone and cheat or key on players as well. I believe in college man is the best, most flexible defense played...and probably 95% or more coaches use that as their staple defense. Some percentage below that only use man, but have no feel for that number. Personally. I think I can do almost everything a zone does in man...and there are many things a zone can do like man.
I think the real issue comes down to what do you want to give up...because both have potential issues and THAT is the real debate. Glad you chimed in. I may have asked you in the past...do you know Bruce Taflinger (JV under Basil some)...we used to play a lot of ball back in the 70s when there was one city league, church league and pickup.