I think that the key is whether borrowing against asset backed line of credit in case of Tesla and borrowing based on future stream of income in case of SolarCity is considered "corporate debt" or not. I posed this question up-thread and hopefully somebody versed in corporate financing can answer it.
I think you can safely assume that Elon wouldn't view using the asset backed line as corporate debt. Legally it is, but Tesla really does treat it as a timing facility (to deal with overseas shipments, etc). Tesla will probably still borrow against that. (Financially, this debt falls under short-term borrowings on the balance sheet and that's why they wouldn't really call it corporate debt either).
SolarCity is different when you talk asset-backed. I feel like I'm beating a drum that no one is listening too, but I'll try again...
SolarCity is the
seller in its ABS transactions (these are really complicated and I'm simplifying, but for cash flow purposes it is the same thing regardless of how the deal is structured). It is not the borrower -- these transactions are not debt. (Many posters on this forum seem to conflate this issue when they talk about the recent ABL sale to riase $305 million in September and the "interest" rate paid).
In fact, these ABS transactions are likely the primary reason that SolarCity projected that it would be cash flow positive in Q3 and even more so in Q4. Yes, the discount rate is higher than they'd like. In other words, SolarCity is monetizing its huge portfolio of solar leases -- an asset that the market has practically been assuming is worthless.
Putting it all together, I think it's rather significant that Elon made the observation that neither Tesla nor SolarCity will need cash.
He meant it on both a stand-alone and a combined basis. In fact, on a combined basis, Tesla has likely found their short-term source of capital. I mentioned it up-thread, but I'll reiterate it here. Tesla can likely accelerate the process that SolarCity began and liquidate the remaining solar lease portfolio and generate a great deal of positive cash flow (probably more than enough to deal with all near-term cash needs).
SolarCity probably hasn't been inclined to be too aggressive because I believe it would have a worse earnings impact for them. (Tesla is probably writing down all these solar leases as part of the purchase transaction and therefore wouldn't have the earnings impact).
As an aside, few here have mentioned it (and all the articles seem to miss it too), but Elon subsequently replied on Twitter that they "probably" didn't need capital in Q1 17 either. That's almost as big a deal as not needing it this quarter because you should assume most of their M3 capital requirements would occur by Q2 17.
Finally, complete speculation on my part, but I think they believe they have enough cash for 2017 Gigafactory progress and initial M3 launch -- at least enough until Fremont doubling.