Yeah , I think it,s ment for tight angles and needing more spin to get it in
Not really. Windshield wiper forehand is just the motion that is somewhat common when hitting a traditional modern forehand in today's game in order to generate topspin. Placement wise it doesn't matter, deep/short/angled it can all be done. However, if you notice Federer, who arguably has the best "windshield wiper technique," oftentimes when he wants to hit a short angle crosscourt and he is on the run, he will roll the racket up towards his head kind of like how Nadal hits his forehand normally. However, when he has time to step into the ball, the generally seems to prefer the windshield wiper technique when hitting cross court.