I was thinking these exact thoughts today. Also I think it may be possible that Mack and his staff were not evaluating prospects very well...W'S AND Losses make you or break you.
I read they weren't evaluating them, period. They simply went with what the recruiting services said and did no personal on-site or film evaluations. This is why they did not give Manziel or Jameis Winston the time of day. Both were desperate to play at Texas. Incredible, huh.