This was posted in the wrong section, but XDA doesn't have a comedy section. Leaving the phone charging for about 10 minutes after it indicates a full charge makes sure that (assuming the phone is properly calibrated, which most are) the battery isn't 99.9% charged but actually 100% charged.
The rest of the nonsense is a case of confirmation bias - since he went to all that work to get more battery life, he's certain that he's getting more battery life. (And in this case, "more" means about 2 minutes.) Turn the screen on once to check the time and you've used more than that 0.1% extra power.
And all that plugging and unplugging in a microUSB connector can cause the connector to fail faster. (It can't hurt if you use wireless charging, since there's no connector to break.)
Since the charging circuit in the phone cuts off when the battery is fully charged, it doesn't hurt to leave the charger on for as long as you're near power. But once you stop charging it, if you want the battery to last longer (not the charge time, the number of months the battery lasts - charge it again when it's down to 40%-60%. If you don't believe me, read
Battery University - How to Prolong Lithium-based Batteries and look at the chart. Then figure out which will give you the longest life.)
