Now, if one assumes that reasonable refresh rate is once per calendar quarter, Tesla needs to sell 1,300 demo cars each and every quarter. These 1,300 cars per quarter *are* part of the demand. Hence my assertion that that "demand can't quite support 2,000 cars/week production" conclusion is not accurate.
This. Maintaining an inventory fleet for demo purposes and as loaners is a cost of doing business. They are bumping back a custom customer order in order to build an inventory car. It's only if they don't have enough custom car orders for a given production slot and then building an inventory car would they then be demand constrained. Given the ongoing wait times and customer deposits, that's very unlikely.
You can subscribe to ev-cpo's historical data (U.S., Europe, and Canada) for a very small fee. The total amount of inventory cars that have been removed over the past 5 quarters, on an average basis per quarter, is way below 1,300. While each car removed might not be a sold car, every sold car must be removed. Terms of service says that I can't report the actual amount, but you can sign up, pay a small fee and see the number for yourself.