I saw a guy at nationals one year complaining that they found his ball had 2.5 ounces of side weight and to make it legal they drilled out the extra (took a huge balance hole). During competition he was complaining on how the ball didn’t break like before. Sure the lane condition had something to do with that but he never liked the ball after he got back from nationals and on his house shot.
Top weight matters in that in conjunction with the pin distance on how you can drill the ball and whether a balance hole is required.
Back in 2000 I went to the National's and one of my team mates had a Faball Sledge Hammer.
They weighed it and said it had too much finger weight,So he took it over to the Hammer booth and they took a long skinny drill bit and drilled deep down through both finger holes. (You could drop a ink pin in those holes and it would almost disappear.)
After that, that ball wouldn't hook for nothing, even back home on the house shot it would barely move.
From what I've seen of the study's, they don't really say static weights don't matter, just other thing's matter more.