Scheme needs to fit personnel.
Cowboys played both ZBS and PBS under Callahan.
Went from PBS in 2012 to ZBS in 2013 and beyond. But Callahan started using both schemes to change up and become less predictable.
https://sportdfw.com/2013/09/09/understanding-dallas-cowboys-new-zone-blocking-scheme/
Cowboys then went through THREE o-line coaches after driving Callahan away, finally settling on Marc Columbo who finally got the OL back on track.
https://ftw.usatoday.com/2018/11/nfl-cowboys-offense-jason-garrett-scott-linehan-bill-callahan
Cowboys then fired Columbo with McCarthy hire and brought in Philbin which also not coincidentally signaled the end of the OL dominance, each season getting increasingly worse.
FYI -
Philbin is a ZBS coach. But not all ZBS coaches are created equal.
As i mentioned, there may be different kinds of zone block schemes,
The Packers zone block is a different element than a Callahan, or Kyle Shanahan zone scheme
Maybe Callahan does hybrid block but even the article you posted per Callahan made mentioned that Bill's "
zone scheme" is a thing of legendary.
ex-Cowboys OL coach and current Bengals OL coach Jim Pollack was a discipline of Callahan and he may have ran a hybrid OL scheme of sort
but just like Cally, it's gonna be more of one vs the other,
- And this Packer zone scheme may be ill-suited for a power oriented guy such as Tyler Smith.
- Oddly this run game design is utterly nuthin' that was in McCarthy run game scheme in GB ..
Philibin was more the OC than an OL coach, as long time OL Coach James Camben served in that role in GB
and the GB run scheme involved a number of misdirection runs and well designed RB screens - sumthin' that Kellen seems horrid at.. !!
- Frankly i wouldn't mind bringing in a Mike Munchak or even a Columbo to a power-scheme again
after the season. i know Philibin has an assistant OL coach but i really want a productive solo OL coach.
- Only thing with Columbo's take no prisoners demeanor, it may have to be certain HCs that has to be able to handle and deal with him
Ditto for Munchak as well , as he's had incidents with pulling opposing players' dreadlocks
Ironically i believe neither of the aforementioned guys are currently employed with an NFL team .