Don't thank me! I tried to write it up, and it was like a 5 year old trying to explain how aerodynamics work
I eventually gave up and Googled it.
Unfortunately, it does mean that we're probably stuck with the fins for a good while. They aren't pretty, but I don't see them going away, or the holes for that matter. Even if big GT concepts replaced LMPs.
For what it's worth, I don't find the current LMPs THAT ugly. I don't know why, I just don't. I prefer them to the open top with a single seat, and I really didn't like LMP675 style. I like the current LMPs. 2016 Audi R18 was ugly though.