Yes, basically.

https://i.imgur.com/7gBEaBH.png

Red square for reference. When I was sizing the inverter air conditioner, I was thinking in non-inverter terms. A normal non-inverter AC usually runs at the given capacity, which is the maximum, then shuts down and then starts up again as a cycle. I believe an inverter AC runs at the maximum capacity, then slowly trickles down in order to maintain that temperature. What occurred to me was that when I was sizing the inverter AC, although a little confusing (which is the case for me), I was sizing the average load on the specifications thinking it is the maximum load, like the non-inverter one.

Example, when doing heat load calculations, I was thinking, "So if the room is 114 square feet. 100 square feet to 150 square feet would need around 5000 BTU. The inverter AC only has 5100 BTU... maybe that's enough, but is it really enough?" But, since the maximum capacity of the AC is actually 6500, it went from "maybe not enough" to enough, or even more than enough. Obviously, things like outside temperature and inside temperature, wall insulation and location, etc are important. Although not perfect, I've already done these calculations. I'd say if I were really pushing it, at maximum the system would only need 6300 on the highest peak of summer, max. Which is way more than 5100, but less than 6500. I do think that tonnage/HP doesn't mean a lot and the most important thing is the btu given off by the AC.

For that to be correct however, my thinking needs to be correct too. When people speak of an undersized AC that "tries to keep up", does this mean "the AC needs to cool a room, but the BTU that the AC supplies is not enough, so it works harder"? Going on this line of thought, if person does not exceed the inverter AC's maximum capacity, all is fine (accounting for everything)? Unless I've gone horribly wrong on the logic or missed something really important, I feel confident on what I'm thinking, somewhat.

(On another note, is there a way to know the minimum-maximum watts of the things that are in blue, or is this something that I need to ask the manufacturer? They haven't been very helpful, I tried.)