There's no real reason to consider csound any different from any other synthesiser in this respect: someone who understands how to program a synth just needs to know "which knobs and switches" there are - whether they're physical hardware, a virtual instrument's GUI, or xml statements doesn't matter all that much... the only thing that matters is being able to set and control VFOs/LFOs, ADSR, resonance, unison, etc. =)

And dear lord do some people understand synths.

any links to anyone who both has this deep understanding and teaches it?

Youtube is actually an excellent resource here - search for "intro to Synthesis" or "intro to synthesizers", and move up to "advanced synthesis" (or related terms) and there are boatloads of excellent videos teaching you more than you ever thought was possible.