Stadion's Sports and Martial Arts Training Discussion

Very, very few sports people in the world, people with huge executive positions, even most people who can do the splits know anything about stretching. In sports like football (Soccer), Rugby and team sports they only need a bit of flexibility and even improper training will give them enough. They'd...

Are high leg raises more beneficial to flexibility than high kicks? Why? Is it true the best time for relaxed stretching is after a warm bath?
Thanks