Off-topic:

I don't have any use for this, personally.

I am both a longtime user of both tmux and iTerm, although I haven't ever used iTerm's tmux "integration". Anyone have a good reference they could point me to that explains how it works and how to get started using it.

FWIW, I normally have a single iTerm window with two or three tabs open. In tab 1, I have a tmux session running which is mostly just SSH sessions to various servers (where I usually have tmux nested). This tab is where I spend 98% of my time. The other tab(s) are just for quick little things I need to do in a "clean" shell/window. I've looked a little into iTerm's tmux integration but I'm not sure it'd really be any benefit to me. (I'm not a developer but I am a network engineer and server monkey, so I've usually got anywhere from six to 30 SSH sessions open at once.)

Interesting. I'm not going to lie, I prefer just using tmux. I'd rather take a few minutes at the start of a session to get my windows/panes just right than to run this script. Plus, it doesn't look like there's any way to change the width and height of the panes, which I use very often in tmux.