Don't think that's what he's saying at all. But most 5th year guys are going to be good, solid pieces rather than some sort of dominant force. If you get them on campus in August, there's only going to be so much time for them to learn what's going on. If they aren't ready to be a solid piece by January, was it really worth adding them to the mix?
You would rather take a young guy and give them those reps and build for the future, often times. Just my opinion.