From my experience it wouldn't be worth the time and effort for one small plant. You're talking waiting possibly 3 months for a few grams of weed. That's ridiculous.
I said this was purely for discussion purposes, so lets discuss.
Typical autoflower strains take 8-9 weeks from seed to harvest, and some take less.
Waiting three months would be about right if you're include drying/curing time, but I don't see why that length of time would problematic (let alone "ridiculous"). You're going to need more or less the same amount of time to grow ANY strain, under almost any condition, and many grows take a LOT longer than that.
Also, you could start grow #2 right when grow #1 is being chopped (or sooner) meaning a harvest cycle of only 2 months (or less).
As to why anyone would to grow a plant this small, well, again for discussion purposes, consider it the ultimate "stealth" grow. If you lived in a dorm or small apartment you might not have a free closet available for growing, or even the space for a grow tent. In that sort of situation, something like a Rubbermaid sitting in the middle of your floor might look a little odd.
People grow in computer cases, desk drawers, stereo speakers, and other small chambers for this sort of reason, and I don't think that its necessarily "ridiculous" to do so.
As to yield, obviously if you're a serious smoker or medical user then granted, one tiny plant won't be enough for you.
But on the other hand, lets say you can yield 7 or 8 grams from a really good dwarf plant. I don't think that's an unreasonable yield expectation. If you're only an occasional medical or weekend type smoker, then a quarter ounce every two months might be plenty, *especially* if its truly top-shelf in terms of potency.
Even in that limited of a quantity, growing your own still may be more practical/safer than trying to score from a stranger, let alone less expensive.