Initial cost for 300 points made in year 2000 = $20K
estimated maintenance fees of $1400/year= $58,800
$1876 per year average per stay.....even if I'm off, I don't see how you're getting $3,000/year to stay there.
The reason you are not getting the same figure is that you are ignoring the
time value of money. In other words $20K in "year 2000" dollars is worth more than $20K "year 2042" dollars.
Mary Waring's excellent DVC analysis explains this really well, but I'll try to summarize it.
http://www.mousesavers.com/dvc.html#opportunity
The idea is that, you could purchase DVC, or you could invest the purchase price and use the income from that investment plus the annual DVC dues you would have paid anyway to just rent DVC points from some other owner. If you know how much your hypothetical investment will earn, you can compare these two alternatives directly and determine which one is more cost effective. This is an apples to apples comparison.
The tricky part is picking an earnings rate, and so you have to make some reasonable assumptions. If you just used the purchase price to buy savings bonds, you'd be keeping pace with inflation, earning about 3% tax-free on that $20K per year, or about $600. If you had invested it in a stock index fund, and gotten "average" returns of about 10%, you'd pay 1/5 of those earnings in capital gains taxes, so you would make about 8% per year.
I like to use the 8% number, to be conservative about the costs. And, at that rate of return, with current resale pricing, it is cheaper to rent from another owner if you can find points at $10 or less, but cheaper to buy if you can only find points to rent at $11 or higher. Here's the math: an OKW resale point costs $75. 8% return on $75 would be $6. Annual dues are about $4.24 if memory serves. So, the "real cost" of an OKW point is $10.24.
There are two more advantages to the renter, but I tend to ignore them, as I will explain.
First, at the expiration of the DVC term, the renter still has $20K in the bank. The DVC owner has only memories

. However, the time horizon on expiration is far enough away---35 years even for the "earliest" expirations---that that residual value is dwarfed by the ongoing and opportunity costs, so I tend to ignore it. It doesn't change the results much, and just makes the computation harder.
Second, the renter has more flexibility. If for some reason the renter decides he doesn't want to go to DVC anymore, that's okay---he can use his investment proceeds for some other purpose. If the owner decides this, he must either rent, exchange, or sell his points interest. I ignore this too, because no one would ever want to stop coming to WDW.
That said, you seem to suggest that anyone who thinks about more than "just money" would agree with you:
No doubt, based on money alone, offsite is a better deal.
I'm
not basing my decision on money alone. I am comparing the
value, to me, of staying onsite to the
cost of doing so, and I am finding the value wanting.
Different people value those benefits differently, and that's why Baskin Robins has 31 flavors.
Don't get me wrong. I enjoy staying onsite. And, when I can do so via an II exchange, I am happy to do so. An exchange into DVC, after adding up all the costs and fees, ends up being a little more than an offsite stay plus rental car and parking. In that case, taking the exchange is an easy decision, even though we end up renting the car anyway. There is some value there for me, just not enough value to pay market rates.