"Defending" corners

[Enter the Frei]

We put every man in the box when defending corners. If we even put 1 player up the pitch, that will draw back 2 of their defenders. We can't take corners, or defend them, so, there needs to be major work in training this week.

I don't understand that either but a lot of teams do the same.

Perhaps the defence has an advantage the more crowded the penalty area with any collision likely to be a free kick in its favour.

Its a stats thing. The number of goals scored from breakaways is so small that to pack the 18 yard box with all the players outweighs the advantage of having someone upfield.
Same as why most teams dont have a man on each post a lot of the time.

Who remembers Northampton in late 80's early 90's who used to leave 3 up on the halfway line?

It could help us a lot in defending corners though. Just having a man up field to hold up the ball when it's cleared should help us to keep possession and defend corners more effectively.