[Pictured (second from left): Save Khaki's David Mullen demonstrates how to properly rock "the half tuck" in the pages of GQ.]
To say the half tuck is complicated is an understatement. When done right you are a styling chap with just the right amount of sprezzatura and when done even a tad bit wrong you're a living, breathing Old Navy mannequin. I wish there were some concrete rules to this advanced sartorial move, but alas not a single one is firmly established.
The half tuck is truly a shot in the dark as far as I am concerned; sometimes it works and sometimes it fails...hard. Someone may be able to tell you exactly why, but definitely not me. I have found that the best way to go about half tucking to to give it a go and then to inspect the results before you head out the door (not too thoroughly because that would defeat the purpose. In fact, maybe this entire post is defeating the purpose). If it works you will know and if it doesn't simply decide to go all in or all out.
Over time you may develop a Jedi like "feel" for the half tuck and who knows, it may even become natural someday. Regardless, the whole "perfectly imperfect" thing is highly coveted by many stylish cats due in part to how tough it is to actually pull off correctly. If you don't subscribe to the half tuck and prefer a look much more put together I don't blame you. There truly is a time and a place for everything. Maybe the half tuck's is when getting shot by The Sartorialist...
[Pictured (above and below): The half tuck's cousin, the front tuck]