It's always been a chore to keep sessions (and tmux windows) at a minimum to avoid context switching and the cognitive drag/fatigue that comes with too many. My goal is 2 active sessions to avoid context switching, but it's so easy to just take on more tasks and try to cycle between all of them, and accomplish less overall. I've had upwards of a dozen, and it is very draining. Even more panes within windows to track subtasks becomes unruly. The other problem is that work keeps ballooning as agents pick up related/unplanned work along the way all the time. I try to reign things in by having the agent create tickets that we will revisit during planning sessions later. By keeping tasks minimal, it feels slower, but then I can think deeply about the problem without the cognitive residue coming from all the other sessions.