Been thinking about this a bit. I am not sure I like the part in red. I have never heard anyone say such a thing. To elaborate, in my experience a PV system is either a supply side connection or a load side connection. I am certainly aware there are "load side rules" and "supply side rules" and that there will be "load side rules" within/after a supply side connection. Perhaps this is a semantics discussion.
Thoughts?
While it is true that it is rarely if ever discussed as if all PV systems have a supply side connection, I think it is ultimately the most sensible way to apply the rules.
For example, suppose you have a service with two MCB panels under the 230.40 exception. Both panels have both loads and PV systems. How to make sense of the rule, which has always been in the supply side section of 705, that the sum of the PV sources output shall not exceed the rating of the service? You would agree that this rule makes sense regardless of how the systems are connected, right? One should not make the argument that because the systems are connected load side, the supply side rule limiting total output does not apply. Right?
(And this is not all that far fetched. Imagine a 200A service, with two 100A main breakers, but someone uses 200A panels, thus allowing up to 280A of backfeed according to the load side 120% rule.)
The best way to make sense of it is to treat the installation as if there are two supply-side connections. Hence my contention that there is a supply-side connection for every system, whether it is the only one or whether it is in series with load side connection(s).
Another point: if load side connections in series each need to be considered under 705 at each point along the way (as many of us here have argued and which was corroborated by past code language) then so does the supply side connection.
In the past, the definition of inverter output circuit corroborated this interpretation, because it said (more or less) that inverter output circuit conductors were all the conductors between the inverter and the service point. Hence you still have inverter output 'connections' all along the way in series. In the last cycle they removed that language and essentially made the definition meaningless, in my opinion. I just noticed that recently. In my opinion it was a mistake.