I think this is an extremely smart idea, and I agree that this is the demand lever mentioned by Musk a while back.
I'm expecting the website Model X configurator to go live Thursday after market or Friday during market, and I think this was the last step before we receive a lot more information about the Model X.
Why is this important? I'll list out my opinions here:
A) It's only referring for the Model S. The typical effect of demand waning in the face of pending, new models being released is heavily being combated by this program. (This program is not counting Model X reserves/orders--huge clue right here)
B) It does indeed indicate that they are finally demand restrained on the Model S, or are expected to be quite soon. This does not mean that they were demand constrained before Q3, but rather in the massive quarter over quarter jump expected for Q3 and Q4 Model S. This is to be expected--they are ramping up significantly year over year for Q3, just like from 2013-2014 in the same quarter, and the wait times have not exactly been that long compared to earlier in the year. No matter how awesome the Model S is, they're still hitting the upper limits of what luxury sedans in the same price range sell for in the US, and their China/western European exposure is still developing and can't yet pick up that torch. The Model S being demand constrained is not an issue in a few months as the Model X production fires up and deliveries begin, as both investors and Elon are expecting Model S demand to decrease relative to the Model X anyways (Musk's comments a while back in his belief the Model X will surpass Model S popularity, and SUV popularity v. Sedan).
C) Although I've been skeptical of a Model X delay recently, I think this right here demonstrates that there is not any Model X delay. My logic here is that this demand lever applicable to the Model S, will allow Model X information to go out in earnest without allowing target delivery numbers to slip on the MS.
D) This model serves Elon's model well. This will have a much proportionately larger impact out of major city centers. Tesla owners already do this for free, and by far the best electric car salesman is your neighbor next door who you see every single day commuting and road tripping--not a salesman.
The business I work at saves tens of millions of dolllars by developing and expanding self-serve options for customers that replace interactions with customer service reps. They put an X dollar amount on every transaction, and lo and behold after working there for a year, I ran those numbers myself (number of personal transactions divided into my salary/benefits) and the two numbers matched pretty closely. In the grand scheme of things, not having to hire as many new workers to accommodate growth saved money by implementing those self-serve options.
It works like this: by employing tools like the referral, they can compare growth of revenue to growth of overhead costs. If the growth of overhead slows compared to revenue faster than expected with referral bonuses, TM is at the very least breaking even (they've done the research here already) and at the very most they're creating new loyal customers who'll be multiple Tesla vehicles over the next decade.