What you were told is correct. In general, PV breaker sum total + main breaker, cannot exceed 120% of the busbar rating. So this means for a 200A with a 175A main breaker, you'd be limited to 65A worth of interconnection breaker. Observe that 65A+175A = 240A, and 240A is 120% of 200A. Good luck finding a 65A breaker, because that is not a standard size. And this is the crux of what I will discuss in the next paragraph. So in a practical sense, for NEC2011 and earlier, you'd be limited to 60A worth of interconnection breaker, which is 48A of total inverter current. That's an 11.4kW single phase inverter on a standard 240V single phase system.
HOWEVER, in NEC2014, the code has changed ever so slightly on this. They've rewritten the language so that rounding errors like the above, are no longer a show stopper. Instead of using the total of interconnection breakers, you now use the factor that drives their sizes instead. So 1.25*total inverter rated current, rather than this value rounded to the breaker that you use.
So in this example, you are no longer limited to 48A of inverter current. You are now limited to 52A of inverter current, which is 12.48 kWac worth of inverter on a standard 240V single phase system.
The big question for people in places where NEC2014 does not apply is, "can I take advantage of a favorable future rule?".
I'm not an inspector, and I certainly cannot speak for any jurisdiction, so the following is entirely my opinion. If it were my judgement call, I would allow it, provided that all related future rules are also followed, and the installation meets the intent of the substantiation for the future rule. I don't see a need to follow unrelated future rules (such as rapid shutdown), simply because you intend to take advantage of the 2014 rule for 705.12(D). Although I can understand if an AHJ requires you to follow the entire NEC2014 when taking advantage of a future rule, even if it requires a stricter installation for complying with unrelated rules.