we are talking a QUALITY Curry here not your T/A mass produced stuff.
I don't doubt it for a minute. This place sounds top notch. I also don't doubt that they dry roast and grind their own spices, and catch their own baby squid!
But it really depends on what you (and I, and others on the forum) are trying to reproduce.
For me, that's traditional BIR fare. (Madras, CTM, Vindaloo...) And to me that means a base, cheap spices, and likely plenty of corners cut (oil, etc).
Where I live (Toronto), there are dozens of "nouveau" Indian restaurants. The food in most of these is excellent, and probably not dissimilar to the restaurant you got your lesson from. But I'd take a grubby Chicken Madras, pilao and naan from a high street BIR (that produces the taste) anyday!