If you take a 3rd round talent with a 1st round pick, that sounds like the classic example of a reach. In that situation you should try to move down, or trade that pick for a future pick. A 1st rounder in 2008 is likely to be more valuable than a 1st rounder in 2007 if you can't even find 1st round talent in 2007 with that pick, no?
Just because linebacker is a position of need, you shouldn't take a less talented player. IMO, if your choice is between Bradly or Jackson (a fit/need but a 2nd/3rd round talent) vs say Meachem or Lynch (a 1st round talent but not a need) you should go with the best player every time. Good players can always be moved later. Look at Branch and Lance Briggs. Bad picks will haunt you forever. Because you're unlikely to ever get that pick's value back. Well you could trade your failure for another team's failure but that didn't work out so great with Sullivan did it?
Please don't make Katzenmoyer out to be this sure thing stud. He wasn't. Lots of GMs had doubts about him because he had a very "ordinary" final season. It was a Grier pick and I wouldn't bother wasting my time defending Grier if I were you. Here's the relevant quote from an article written pre-draft.
"Now, after a strangely ordinary junior season at Ohio State, Katzenmoyer inspires loud hesitation among NFL general managers, personnel directors and scouts. They struggle to match his physical skills with the way he played in 1998."
http://www.findarticles.com/p/articles/mi_m1208/is_12_223/ai_54245993
Fact is despite the doubts about Katzenmoyer, Grier decided to draft him based on need. We know what happened afterwards.
If you want to tack on more Grier gaffes, how did that tebuckey jones pick work out? He was a swell cornerback wasn't he? Oops, that's right he never did play corner, although we drafted him because we "needed" a corner and were convinced we could convert him.
Okay and just so people don't lose track here... I am NOT saying don't draft a linebacker.
I'm saying don't REACH for a linebacker. There's a big difference.