I think its a 'quick fix' to a problem they aren't sure how to solve...
Will it help? Maybe... but probably not to the extent they want it to.
As for 4 wheels vehicles, as long as you maintain your own lane, then you will be unaffected... If you're stupid enough to change lanes, then bump stops aren't going to stop or save you in the event you realize it was a bad idea...
You can't stop stupid.
