obviously

however......there are different skill sets and like you said.....the quicker LB usually goes on the weakside and the bigger LB usually goes on the strongside

in high school most people run a 4-4 or a 3-4 or sometimes a 4-2-5

and your positions are limited to the kids available at the school

however.....in the NFL each position is specialized and each player has a specific skill set to match that position

there is a reason players are scouted as a Cover 2 corner or a WLB

they have the skill set to play that position but not necessarily the other man-corner or SLB

I agree that the do specialize but not that it should close doors when talking about your depth chart much the same way that a guy might play every position on the OL I think we are talking (Ideally) and (filling in getting a job done.)

of course.....if you play LB you should be able to fill in anywhere....

just like a center should be able to play guard

but there are definitly players with skill sets better suited for one or the other

not everybody that is an OLB can play MLB and vice versa......not everybody that can take on blockers and cover in space.....thats the reason sergio kindle is scouted as a SLB/DE and sean weatherspoon is scouted as a WLB

different skill sets