Amongst conventional cars, there is a tradeoff between performance and fuel economy. You can high performance or high fuel Efficiency,.but not both. Naturally consumers prefer higher performance, but when the price of fuel is high they are more willing to sacrifice performance to save some money at the pump. Thus, sales of high performance cars goes up when oil goes down.
What is utterly unique about Tesla is that their cars are both high performance and high fuel economy. There is no tradeoff. You do not have to sacrifice performance just to avoid pain at the pump. The FUD argument is to pigeonhole Tesla as a fuel economy vehicle and as such to suggest that its appeal will suffer the same fate of vehicles that sacrifice performance to obtain fuel efficiency. They are trying to penalize Tesla for fuel efficiency. But this is simply a denial that Tesla is primarily a high performance player. When oil prices come down, it is not simply that pain at the pump is reduced, but everything becomes cheaper, consumers have more discretionary income, and the economy is just more favorable for splurging the things you want. So car buyers feel freer to splurge on higher performance cars because they can.
High consumer confidence is favorable to Tesla. When the price of oil falls, car buyers set their sights on buying higher performance vehicles, not because they are cheaper, but because they are more desirable. In such a buying climate, Tesla can compete quite handily. The Model S is among the highest performing cars in world. No doubt the Model X will be the highest perfirming SUV on the market. How about the Model 3? Should we not expect that the Model 3 will be the highest performance vehicle in its class and price range? So if the car buying public is in the mood to buy a higher performance vehicle, Tesla will stack up quite favorably. No compromise.
I think the key thing to watch for is that car buyer sentiment turns toward higher performance. As this happen, Tesla will have no difficulty finding willing buyers for their cars. There has been some concern that the luxury performance segment is just too small to accomodate Tesla's growth ambition and this becomes the motive for trying to move down market. However if cheap oil ushers in an era whereby more consumers move up market, then this would be quite fortuitous for Tesla. If oil is still cheap in 2018, it could mean that Models S and X are within reach for a greater number of families. Consider a family with two cars. As the price of gas comes down, they have more monthly income left over with which to buy there next car. They may find that the savings in gas on the gas car they keep makes it easier to afford the monthly payment on their new Model X. Thus, the lower gas prices actually facilitates going upmarket to a performance EV. Conversely, if gas prices go up substantially this would put a strain on their monthly finances. So their confidence as a consumer will be directly impacted by their expectation of gas prices. High consumer confidence emboldens families to stretch into high end Tesla purchases. So let's keep our eye on consumer sentimant moving upmarket.