Have you seen this with Opus 5.5?

I've been mostly working on very large modeling projects (think detailed architeture over 1000 acres) or animation because this really was the "new" capability area that Opus 5.5 "unlocked".

I have been surprised how well it has worked at scale with many sub-agents. However the code base is limited to the rendering engine mostly.

Certainly in the older models they hit a complexity limit, but I haven't really hit it with Opus 5.5. I have had it make data flow designs that I didn't like because they were more complicated than it should have been or the perenial problem of trying to make everything backwards compatible when working on greenfield refactors, but I haven't seen it choke on a code base yet.