For sure, when you're feeding rootbound is not an issue cause it don't have a life long enough for it too be truly rootbound... hell no cannabis does! But you'll see many plants that do!? My favorite part is how they say when roots come out drainage holes its rootbound... I'm like ok! But In reality it takes years to become rootbound! But your version of rootbound is correct In a sense cause it focuses on your feed but most that say rootbound have no idea.
If your plant was rootbound it would be dead! Being rootbound means that it is rootbound, correct? Rootbound is the root strangles the plant.
Wisher is correct with his example though, cause it translate to what people understand