b)Large automakers know this but simpler for them translates into less maintenance which means lower profits. Automakers therefore will pay lip service to electrics, drag their feet and kill off any real electric competition if they can. The world's environment is not a shareholder in the large automakers.
So his "master plan", (the Truth but not the whole truth) he published in 2006. What he left out was that he knew as he moved to a high volume model that's when the large automakers would try to cut Tesla off at the knees and then go back to resting on their laurels.
If his high volume model was mediocre and expensive to build Tesla would be dead in the water. He needed an excellent car but even more than that he needed Tesla's cost to be much lower than the majors could match so they couldn't low ball the market long enough to cut off Tesla's oxygen.
When Tesla got 400k Model3 pre-orders that's when he decided to double down on the 'low unit cost/large production investment' strategy for the model3. Making this work is critical to Tesla's strategy. You can be sure Musk and his team put a lot of effort into the production tech knowing it was make or break for Tesla.
The Economist is under estimating Musk and they should give him a little more credit given his track record. Telsa is not a slam dunk but it's also nowhere near as fragile as they make out. Musk also has a bit of equity in SpaceX he could lean on if the markets demur at the end of 2019.