Tesla is currently stuck around 800 Model 3 cars per week.[1] They ramped up to that level in late January. Up and down since then. They clearly have some major production line problem, but what it is hasn't come out yet.
They're about to miss a major target next week. "Musk said Tesla was ready for 1,000 a week at the start of the year and would ramp up to 2,500 a week by the end of March." - Bloomberg. They were at 355 a week at the beginning of 2018 and are at 810 now.
Also, assembly lines don't "ramp up" well. Costs are relatively constant regardless of the number produced. Every station on the line has to be manned. An assembly line running at 1/6 speed means a product that costs up to 6x normal to make.
I don't think anyone serious would describe the Model 3 ramp-up as doing just fine. Musk's charisma coupled with the markets perception of Tesla's products as exciting and innovative appears to gives him far more leeway to constantly miss deadlines than would be tolerated at virtually any other automaker. The recent Tesla Roadster announcement was practically an exercise in distraction to divert attention from the Model 3 woes.
Comparing their current poor performance to their past even worse performance arguably does not equate to "doing just fine".
[1] https://www.bloomberg.com/graphics/2018-tesla-tracker/#