The reason the club has desired him, if that is indeed true, is because he is one of the top wide players in the world. You'd be hard pressed to find many players with Bale's productivity; averaging a goal every two games playing is no mean task, most strikers would kill for those kind of numbers. If Van Gaal wants to play 433 as his predominant system with us then I could see very few reasons from him and the club to not be on the same page.
Forgive me for saying this, but half this system talk and the view that he would be useless in right spaces is ridiculous. The poster you quoted said, "no one parks the bus against Spurs"; it boggles my mind that someone who watched Spurs in Bale's final season can hold that view. Even Fergie parked the bus and played on the counter at WHL that season. Bale was regularly bailing Spurs out with his ability to run at defenses and scoring from the long range; he made defenders uncomfortable with his pace, strength and shooting ability. He is not a Messi or Hazard with low of center of gravity and guile in extremely tight spaces, but then very few players are. And actually, who doesn't struggle when space is limited? Are Robben or Ronaldo great in these "tight spaces"?
Despite all the "philosophy" talk, LVG has shown himself to be flexible enough to adapt to different systems. Bale would be extremely useful as a wide player in the 433/4231/433 or as one of the strikers in a 352. This season, we have struggled in games because of our lack of pace and ability to get behind opposition defense, Bale is an instant solution for those issues. He is very good at free-kicks and so is his long range shooting. With Bale we can have other options than hoofing it to Fellaini whenever we are struggling to break down teams. His pace would help us stretch games and push defenses back. At times this season, we have looked painfully slow on the counter except when di Maria was on the pitch. It has been surreal watching us struggle on counter with Mata and Fellaini running at the oppositions Goal.
The system would not work if we keep passing the ball uselessly between the defense and the midfield. Someone, somewhere would need to take a chance, and Bale is a player with skills to do that. The Bayern fan, Balu, has mentioned previously that the system was similarly slow and ponderous at Bayern and most of the time the onus was on Robben to produce something. Bale can be that player for us. We have been so easy to defend against this entire season, the opposition defense and midfield just sit back and enjoy us pass the ball from side to side without every threatening them; if anything the system would have make a leeway for Bale, as it should.
This forum would have you believe that Bale is some run-of-the-mill speed merchant who runs in straight lines and can only excel in an empty ground, when he is much more than that.