It's sort of insulting to minimize my points by suggesting that I just don't like new stuff.
But the 10 years ago you wouldn't have taken your advice. 10 years ago CSS was not ubiquitous. There were not good tools. The ecosystem was just getting going. And yet somehow the tradeoff was worth it for you.
Technical designers learn sass quickly. They like it and so the tools will follow. The ecosystem will grow. Already Sass experience is considered a plus in job reqs for many forward-thinking startups. Sass and Compass will mature in the next few years, and you're objections will fall by the way side and a few years after that, instead of having a competetive advantage, you'll be at a competitive disadvantage by not using something like it.
I don't know if Sass and Compass will ultimately be the tools of choice for generating CSS, but I'm certain that there will be tools like them.
If that's not a back-handed compliment I don't know what is.
Here's the thing though, I'm not risk averse. I am the first one to jump into a nascent project and throw down code. The problem here is the cost benefit just isn't there for me yet. I feel I have more competitive advantage to gain by working on greater pain points (for me personally) like lack of continuations in Rails, or even something a lot more ambitious like writing a usable web framework in Haskell in order to gain the advantages of pure functional programming.
In other words, just because I don't a big competitive advantage in your project doesn't mean I'm not an early adopter.