Pure technical growth remains possible in a material steady state, but pure technical growth cannot deliver relentless growth quarter by quarter, since technological progress in technical efficiency proceeds in waves, so if relying on material expansion for growth is no longer an option, relying on growth to provide for ongoing full employment is no longer an option, and so the employment insurance program is a critical part of the model.

I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.