Agree with your post - to add to it, remember how Austin Ainge emphasizes that they track these kids for years so they have a great deal of info on them even before the draft process.Ainge said his usual GM-speak following the Fultz visit by confidently saying at the conclusion, "He’s talented, I didn’t find anything today that I didn’t already know, which is the same case with almost every draft workout. … He has a personality, has some charisma, he’s fun.” Read into the bold as you wish.....to some it may have meaning to others not so, I find his choice of words interesting as if he already knew he had Tatum > Fultz prior to even meeting with Tatum in Boston. Was it Tatum's skillset or the fact that our backcourt was already loaded 4-deep? One could argue that with all else equal Tatum was the obvious choice based on roster fit which I feel certainly "could" have been a factor.
In addition to the bolded, DA also said in his post-workout comments: "I learned that his scoring average is really good against a chair. Good shooting percentages against a chair. High efficiency.”
I've got my theory and I'm sticking to it. Never know if I'm right or wrong, which is the great thing about internet messageboarding.