Maybe for Chin and Antigua, but Underwood had not be known for his recruiting success at his previous stops either. He has been known as a very good tactician with good game skills (so the question will be whether they transfer to UI) but not as a recruiter. When Joe Henricksen made that statement about question marks on BU's recruiting ability, he had not started coaching/recruiting at UI yet. I do not think anyone can look at the current situation at UI and say with a straight face that Underwood has been a good recruiter.
Underwood needs to pick it up recruiting-wise, certainly some patterns (e.g., Fall recruiting misses) seem to be repeating. That is the concern IMO. I personally have no doubt that IF Underwood does get the talent, he will be very successful at UI.
I don't disagree with you at all, but your points got me thinking about some of our past Illini coaches and whether or not they excelled at being a 'closer' on their own merits. Would you categorize Lou Henson as a good closer? Lon Kruger? Bill Self? Bruce Weber? John Gross? Some were probably better than others, but none of them, other than Self, really stand out as that great salesman type closer. Even Bill couldn't close on most of his high targets while at Illinois. I think it was a big part of the reason he went to Kansas. I do think that the level of recruiting success of all of our coaches from Lou to Underwood has had a great deal to do with our assistants and the image of the program during each time period.