Is Blocking below the waist going to be illegal all the time?

[Berkut]

I am no expert on the strategy of line play, but would removing the ability to block before the waist in the circumstances it is currently allowed really change the game so much, or give the defense to great an advantage?

I thought not letting backs go low was a pretty big disadvantage - seemed to me like that was almost the only way some small backs had a chance to deal with some end or linebacker. But it hasn't really seemed to have a great impact at the high school level.