Leaving extra lace in front is good because it helps prevent lifting.
Think of your hair as a long crow bar that is prying up the lace (the hair's weight and movement is constantly prying up the lace). In order to make it tougher for the lace to be lifted, you need more lace in front. Imagine laying a book flat on the group and prying it up. The book will pop up easily. Now imagine a rectangle (same weight as the book) but has dimensions 2 feet by 3 feet. If you pry up on side, the opposite side will still be touching the ground.
Hope this analogy is convincing as to why a little more lace in front is better.
Leamon