I think there's a reason this model doesn't work for 'software developers'. There isn't really an 'up' - most developers don't WANT to manage other developers,

I think there's a reason this model doesn't work for 'software developers'. There isn't really an 'up' - most developers don't WANT to manage other developers, they want to write kick ass code. That's fairly unique in the business world - in most other departments, there is a trend of 'hoping for promotion', etc. So there is an 'up'.