Riding From "Front to Back"
To ride from "front to back" means that the rider is using their hands to artificially shape the horse's head and neck, rather than letting the head and neck position change naturally as the overall carriage of the horse improves with training (ie collection.)
There is a pretty large range of offenders, from those who quietly wiggle their fingers to ask the horse to "give" and tuck his nose, all the way to rollkur, where the horse's head is cranked down with strong force.
In every one of these cases, the horse's neck is shortened from front to back (obviously to varying degrees), which jams the horse up, and prevents the impulsion from truly reaching the rider's hand. The rider who shortens the horse's neck with their hands will never achieve the lovely feeling of throughness, with the circle of energy permeating throughout its body.
To understand how causing the horse to shorten and/or overbend his neck stops up the flow of energy through the topline, look at this... (Click on Article Title above (in blue) to read full article)