I completely agree about the steep learning curve and the feeling of dark magic -- how many times have I had to relearn what deparse(substitute(x)) means -- but

I completely agree about the steep learning curve and the feeling of dark magic -- how many times have I had to relearn what deparse(substitute(x)) means -- but oh the satisfaction of broadening my programming horizons. For me it didn't feel like C macros, it felt like "This must be what it feels like to have the power of Lisp"! That's the weird thing about R. All this dark magic is hiding under the hood, but the core R team hid it so deftly that to the casual statistician it's a straightforward data modelling language that "just works". I'm not sure that it's possible to get rid of the dark magic and retain that data-modeller friendliness.