Cooley talked at length about this signing today, and said that he expects McGlynn to push Licht or even displace him.
Here's how he assessed the guy:
Pros: Big, strong, agile, good technique - really good feet, moves as well as a much lighter man. Good at striking out with his hands, can reset and strike again quickly if his first effort doesn't take.
Cons: Occasionally has a serious lapse of technique and is capable of completely whiffing on his block, as in "Where'd he go?" Cooley alluded to some other technique lapses that weren't mentioned, but he thinks could be easily fixed with good coaching. He thinks that McGlynn is probably closing his eyes just before contact, and has to learn to keep them open (don't laugh, Cooley claims that he had to learn the same lesson - he says it's a natural reaction to close your eyes before "running into a wall").
He says he likes this signing, and won't be surprised to see McGlynn starting by week three.