Well, have you used it?
Yes, I have, in three of the four planes I have owned, and others I have flown. It works. But, with a reduction in effectiveness and safety. My present carburetted Lycoming 360 starts best when cranked for 5 to 10 seconds, and then a primer prime introduced. I have perfected this technique over the 550 hours I have flown this plane since 2008, as there is no stated factory procedure for starting it (that was actually mine to develop for it, but the project was not finished to STC approval, so no flight manual was ever developed for it). I have a particular interest in consistent good starts, as some of them are floating. I have certainly flooded it with the primer, and tried pumping the throttle during other experimentation. Using the primer sparingly after the engine is already cranking works best. Certainly, running the battery flat, or ruining a starter motor is to be avoided, as hand propping this plane would be impossible, and help may be a long way away at some destinations.
I certainly agree that it's possible for a pilot to get to know a plane so well, that even a non approved technique results in consistent success. I used to have the 310R I flew down pat. Anyone reading this, who knows their plane that well, knows this. But, to suggest that a student pilot should start developing their own starting techniques invites carb fires, or overheated starter motors.