The graduate transfer rule is the unrestricted free agency of college football, and to not leverage it would be putting yourself at a competitive disadvantage relative to the rest of teams in the country who are - which is pretty much everybody, even the academic schools such as Stanford and Notre Dame are taking graduate transfers in football and other sports.
It's an outstanding way to utilize otherwise unconsumed scholarships among the allotted 85, to supplement your depth chart with physically, academically and socially mature players, even if they're not superstars on the field. Only utilizing it for elite players is not a viable strategy. If they're an elite player then they're not likely wanting for playing time at their current school (the most common reason for transferring), or they're off to the NFL. Typically what you're getting is a serviceable (or better) 2-deep-caliber player who may be blocked a bit on the depth chart by another player(s) at his current school, may not be a scheme fit for a new coaching staff, or who simply wants to challenge himself at a higher level of competition (ex: Gehrig Dieter, an uber-productive All-MAC WR at Bowling Green who played his final season at Alabama in 2016).
Were it not for this avenue, Texas would enter this season with Garrett Gray as its #2 TE. Think about that. Instead, we'll have Kendall Moore from Syracuse, a physically mature and capable receiver/blocker, who saw ample time for the Orange over the past several seasons as both a TE and special teams player, and who is fully ready to step right into the Longhorns' 2-deep alongside Andrew Beck - something no other TE on Texas' projected 2017 roster can say.