The battery pull imo will always work in all cases. Not that I've had this issue yet.
My reasoning for this is if you have a faulty battery and change it with a replacement the switch will will auto recalibrate to the new battery.
If it did not auto calibrate at this point, and thought the new battery was at a low level when in fact it was 100% it would never boot on battery.
As there is no software reset available from the the os or recovery this is the logical way Nintendo have decided to reset the battery memory (custom boot loaders for android have added this functionality)
As for should I press the power. It's good practice to do it, does it matter in this instance? Maybe not but if you took the effort and time to take your switch apart to disconnect the battery pressing the power for 15 seconds is not a huge hindrance
Other ways mentioned may work but they put extra stress on your battery by cycling the battery with charges and discharges