You're still not making much sense. Only five LB's had 100+ tackles last year: Edwards, Bullock, Lewis, Briggs and Brooks. Briggs and Brooks had only 24 and 28 assists, respectively, so that knocks them out of your "elite" category, leaving only three "elite" LB's, according to your criteria.
See for yourself.
In 2000 Arrington was a rookie.
In 2001 Arrington ranked 25th among LB's in my IDP league.
In 2002 Arrington ranked 5th among LB's in my IDP league.
In 2003 Arrington ranked 11th among LB's in my IDP league.
In 2004 Arrington was injured.
Arrington's never been in the top 3. I don't recall ever hearing or reading someone predicting him in the top 3. You've backed off the "inconsistency" charge, but where's the "mediocrity" you're now pointing to?
The kicker is that over Arrington's last three healthy seasons,
even including the one where he had .5 sacks, he's averaged almost 6 sacks per season, which is four less than the 10.5 sacks that those top 5 tacklers
combined to get in sacks last year.
Assuming health - a wild card with any player - Arrington's easily a top 10-15 LB, which is precisely where I see him ranked during most pre-seasons. Greg Williams' scheme does little but to insure that that will be the case.
Finally, let's compare apples to apples. Arrington over those three years has totalled 99, 92, and 88 tackles and assists. If you look at the stats of the LB's with between 80 & 110 combined tackles and assists last year, only two had as many as 4.5 sacks (less, of course, than the 6 sacks that Arrington's averaged over those three years).
One of those LB's was Scott Fujita in KC. Who was the other? Arrington's teammate in Greg Williams' scheme, Marcus Washington.
In short, your argument is a straw man.