I hear ya, but I have to think the Iowa staff is at a high enough level to take linemen (especially scholarship kids) they wouldn’t have to lean up before bulking up again. They’ve had Doyle around long enough to know if a kid fits his criteria or not.
Doyle is good enough to take Ike Boettger from a bean pole (as 6’5” ers go) TE, put 100 lbs on him, and produce an NFL offensive lineman.
Also, take a look at most AlabamaLouisiana/Texas/Florida high school starting OLs. At decent size schools you’d be hard pressed to find one without multiple starters over 300. Those schools put out probably 75% or more of the top 100 OL recruits.