I don't have any more information on the inner machinations of Iowa basketball than anyone else, but I'll take a stab anyway.
I suspect there was some evolution of this. I doubt Lisa Bluder told Caitlyn on day one "just go ahead and do anything you want." But the way the tam evolved, even in her freshman year, Clark was ball-dominant, and the team benefitted from it. And it was obvious that she was very entertaining for the crowd. So I expect Bluder saw her sink some deep threes and, while likely not encouraging her to shoot them, certainly didn't discourage her from shooting really deep occasionally.
FYI, Saylor Poffenbarger was known to launch and make shots within a few paces of the midcourt line when she was in high school. That obviously didn't translate into the same success in the NCAA.