As I said in my previous massive post, Supercharging will be FREE... and battery swaapping will cost you money. That will be THE simple difference that regular people will be able to understand.
You're basing it on that there will be a segment of the population willing to pay money to wait 10 minutes less.
Keep in mind, with Battery swapping you can't leave your car - it's sequential and they need to keep it moving. So you'd be waiting 5 mins for the swap, and then you're going to pull over in a parking spot, get out, stretch & go to the bathroom - you were just driving for 2.5 hours, and about to drive for another 2.5 hours. Yeah... you'll get out. So we're talking about a 10 minute swap-stop vs. a 20 mins charge-stop. And if there is as little as 2 cars in front of you at the Battery Swapper, you're dead even. More than that, and I'm heading for the SuperCharger.
Not only that, you're also making a bet that charge time won't double by the time you are done with your deployment in 3 years. Otherwise you've just bought yourself a nice juicy white elephant.
I can't see this being a coherent plan by itself. There maybe some ultra-niche market (much more elite than the Model S market) where some people may be willing to pay $some amount a day to wait that 10 mins less, but I don't see that.
Look at the following scenario:
* I'm driving from Seattle to Los Angeles to go catch some sun.
* I swap my own battery out at Centralia, then keep swapping another 8 times until I get to Los Angeles.
* Then I hang around for 15 days over there, visiting DisneyLand, Catalina, Sea World etc.
* Then I head back to Seattle, swapping around another 8 times until I'm back in Centralia, 20 days later. So you've had my battery for 20 days (which you couldn't lend out), and I've had some of yours.
How much are you going to charge me for that? Here's a hint: Those $40k batteries that you lent to me (and were now out of action to lend to other people for 20 days), amortized over a 5 year life (nobody is going to be happy with an 8-year old 200 mile range battery), cost you $438 over that time.
So either you're going to eat the cost, or you're going to pass it on to me, which even at cost, I'm going to tell you - no thanks, I'm not going to pay $438 to save 4 hours. I don't make $109 per hour after taxes! (Well... this year. Go TSLA!). But we're literally talking about the difference at the stops between finishing a coffee inside StarBucks, vs. having it in the car on the way.
So I don't think the time vs. cost argument holds up by itself. There are people who would pay that, but can you build a $100m business on it? If there was a standalone company that gives you the above as a business plan, would you invest even $500 in them?
However, there are definitely other possible aspects that will push me over:
a) It's in a location where there is no SuperCharger. Absolutely will pay $21 per day to be able to take the 101 through the Avenue of the Giants (No SuperChargers on 101 there). No question.
b) You rent to me a 500 mile battery - even if I have to return it. Now I can get through the Avenue of the Giants, so I'm a happy camper.
c) It's faster and near-free (So you eat the cost. But then... why do we have SuperChargers?)
Battery swapping is too weak to stand by itself. Citizen-T made it stronger, but I still don't think it's strong enough yet. There has to be another aspect to it other than just time to make it truly compelling.