A reach? Maybe.
Does it fill a need? Definitely.
Trent Williams may not be able to match Bruce Campbell with pure physical ability...Oh wait, yes he can.
Sure Campbell had the fastest 40-yard dash time among o-linemen, but Williams was only three-one-hundredths of a second behind.
Williams also out-jumped Campbell by two inches in the vertical-leap and had a better broad-jump. Both of which(especially in big men) are direct measurements of lower body explosiveness.
Aside from that 40-yard dash Williams out-performed Campbell in every event except for bench press.
It is true Al Davis puts a lot of value on combine performances, but the 40-yard dash isn't all he looks at. He uses all measurables to decide who is best.
Look at Darius Heyward-Bey, sure he had the fastest 40 in the draft, but he also had the highest vertical leap among all receivers as well as great size.
Al Davis will take the offensive tackle with the best combine, Trent Williams not Bruce Campbell.
Plus Williams technique is far more polished and he has far better experience. He will be a solid and immediate contributor at right tackle for the Raiders.
But don't get me wrong this guy is not without his flaws. He has taken criticism for being beat on the play that resulted in Bradford's injury.