As I understand it this is a 4-3 defensive scheme, where the most important positions are the three technique and the strongside, weakside, and middle linebackers.

This is specific to the Tampa 2 style system that Eberflus runs. For example. Greg Blache, a bears DC from forever ago, ran a 4-3 system that used 2 2-gap DTs (think 2 Andrews Billings) and no 3T.

What makes it outdated?

There is a balance between complexity in a system that is hard to figure out and simple systems that allows athletes to play quickly. Eberflus’ system is super simple. Offenses have evolved in the last 20 years and OC know how to pick apart what we are running. Eberflus has no creative scheme fixes to cover its flaws. Its not that cover 2 (the tampa-2 is really a cover 3, but thats a whole other story) plays can’t be called. Its that basic cover 2 with nothing to change it up can’t be called on repeat any more.

This system was one thing in Indy where he was getting by without much talent and using lower draft picks. But now that he has high draft picks and high priced FAs, he has shown that there is no next level to his defense and even Indy was a bit of a mirage. He doesn’t do much to disguise coverage, but there isn’t much variability so I don’t know how much it would matter

Is a 4-3 not usable anymore in the modern NFL?

It is usable, just not the super vanilla system Eberflus runs.

And what will happen when Eberflus is sacked, which looks more and more likely by the week. Is it easy to transition to a different scheme or will the defensive roster be stripped down due to scheme fit

If we switch to a 3-4 a coordinator will say something like “it doesn’t really require that much personnel change” and then spend the next 3 years flipping the entire defensive roster. Some players lime Montez Sweat would probably be able to play standing up, but you are getting 90cents on the dollar for the position change. Most of front 7 would be replaced.

If we stay in a 4-3 its smoother. I hated the Edmunds signing at the time and it looks worse now. Most 4-3 systems don’t require a super athletic middle linebacker, he is superfluous at best. If he plays well he will be traded for a low draft pick. More likely he is cut at some point in the future to get out from under the contract.

Our CBs are fairly system agnostic and would be ok in a more press-man system.

Yeah, but we are seeing a similar poor running attack with Daboll in NY (creative ways to run inside zone and duo, but not much else). I think its more of a reminant of his system. With an offensive HC whether its Bieniemy, Waldren, or Johnson would bring along their own run system. Dorsey was calling one of the highest EPA/play offenses in the league. His main failure was not being able to stop Allen from YOLOing the ball to the defense

1. I hope they trade the First overall pick again rather than watch history repeat
2. HC- Eric Bieniemy, OC - Ken Dorsey, DC - Chris Harris (former Bear)

I think Bieniemy has showed his chops both with how Sam Howell as looked good and with how KC has dropped off after turning to Nagy. If he can make Howell look good while he holds the ball for too long with Charles Leno at LT, imagine what his offense would like like without those things!