There isn't more or less oil in tensioner after an oil change. Maybe after you replace the tensioner, oil pump or relief valve, but not after an oil change.

You can crank the engine without spark to build oil pressure at a lower engine speed than idle but consider the wear to the cylinder walls if unburned fuel washes off the oil. I don't know if K-Jet keeps spraying if the engine doesn't catch.

If you do a search on M116 timing chain failures, you'll find them mostly on the early 81-83? engines, not on the later 84-85 engines. There is basic maintenance to keep the chain where it should be which involves changing the oil at normal intervals and replacing the chain and guides every 100-150K miles. I haven't read in this forum of anyone who cranks the engine after an oil change to build oil pressure to prevent the chain from skipping. Maybe that's why you can't find it in the archives

Sixto
95 S420
87 300SDL