EW and MW have nothing to do with LW, and reason being is most people couldn't care LESS about EW and MW....unfortunately

So caps are NEVER an issue in those arenas so that is why they NEVER CHANGE !
LW on the other hand does have a problem HTC has deem over population of the LW was hurting his business, so he split them. Splitting them added a new problem.... the herd mentality took over... everyone wanted to be in the first LW on the list

So of the first 400 people who logged on...or never log off

350 would be in the first arena, the rest would be split in the second arena (less than 20 people per side WOW !!! some fun!) So they installed the "dynamic cap system" to grow the population evenly between the two LW arenas.
1. Split arenas are he to stay, GET USE TO IT !
2. Dynamic Caps are here to stay, GET USE TO IT !
3. Complaining about the caps will never go away, on the other hand, it won't change anything either (see #1 and #2 above) GET USE TO IT !
Couple of things to think about.....
If there was no dynamic caps setup in LW and you logged in AFTER the first arena has hit is cap, you would be playing by yourself (or is that "with" yourself) until the numbers climbed high enough for the arena to have good fights... with zero chance of getting in the other arena because they would NEVER log out.
Last thing... right now US prime time they have 600-700 people log in at a time. Whats going to happen when subscription numbers rise and the two LW arenas maintain over 400 in each arena night after night? Can you say
3 LW arenas? 