Exactly ! They are only single speed tyrannies. On the gas side of things there is literature out by Mercedes that even warns you not to be changing even the oil to soon in the Smart.
Everything most of us have been accustomed to gets thrown out the window when it comes to the Smarts. It's a whole separate breed unto itself, with clever engineering that was never thought possible. We can all take pride in the knowledge that our car will some day grace the halls of the Smithsonian Institute as one of automotive's all time great engineering accomplishments. Forever in the annals of great 21st century technology.
Future historians will perhaps point to this period when hope was within reach only to be sabotaged by fake claims and greed. The precursor to America's ultimate downfall as foretold long ago by George Orwell.
The late brother of a fellow car enthusiast was an oil engineer, of the type who formulated experimental "brands" for testing.
He told me that many lubricants are made with two types of fluids: "2X" lubricants and "1X" detergents. The "X" refers to the duration so that the lubrication additives lasts twice as long as the detergent additives do.
As an example: If the oil is supposed to last 5000 miles before change, the first 2500 miles will include detergent action to clean all the particulate matter so it can be trapped by the filter. All this time, the oil is also lubricating and will continue to lubricate until 5000 when it loses major effectiveness. So you change it no later than 5000 miles.
You don't want to change too early or you get no benefit from the detergent and you don't want to wait until 6000 miles, because you lose lubrication effectiveness.
Recommended brands of lubricants are matched to duration of effectiveness of the additives.
Can you use other brands? Of course, especially if you know the level of effectiveness and the duration of its additives.
This is true in Citroen cars which used LHM+. Some brands of US aircraft hydraulic fluids exceed the specs for the car's hydraulic system. They certainly can't hurt anything.