1) I agree that over the long haul, and for long term investors such as myself, it won't make a difference. In the short haul though, the affect on revenue of building 40's primarily can be a shock to investors, especially if they haven't been prepared for it. If an 85 has an ASP 20k higher than a 40 on average, and assuming margins are the same for all the cars Tesla builds, they may find themselves building 5 cars to get the revenue and margin they that they get for building 4 today. That may not sound like much, and it's not a long term or permanent problem. But that kind of lumpiness in revenue streams without any warning to the investors is a way to build distrust in one's accounting practice.
If my post reads as a sky-is-falling, or that somehow Tesla is in danger of going bankrupt, then clearly I've written what I intended to say very poorly. I see short term lumpiness in revenue (and therefore margins) coming Tesla's way. It is inevitable if they do the right thing and focus on the 40's and other options that they haven't been able to build. My only point is that when I listen to the earnings call and read the report, I want to see Tesla talking about the short term lumpiness. (Transparency!)
In the end, the only way I see this being a serious negative for the company is if they don't talk about it, and then have to explain what happened (past tense) in the Q1 or Q2 earnings call. That sort of a conversation that could easily be anticipated lowers investor confidence. Much as I love the company and look forward to driving Model X, it will surely lower my confidence in the company as an investment, if for no other reason that this sort of dynamic in the business is what they need to be explaining before it happens so we're all ready for it when it happens.