No, it will not if you learn to use your strap properly!
BlackRapid straps have two latches (they call it Bumpers): one in front, one on the back of the carabiner you use to connect it to the camera.
Position the back bump where you want your camera to hang when you carry it, and close the latch.
Than pull down the front bumper, place it right next to the carabiner and close it too.
That way camera will not swing and it'll stay exactly where you want it to be.
Probably there are some better video presentations, but in this one, at 2:24 you can see how it's done:
Yours must be modified as two bumpers defeat the object of how the blackrapid is designed.
There should only be a bumper at the back to stop the camera swinging too far back (and also to bring the shoulder strap back into position if it moves).
The blackrapid is designed so that when you reach down and grab the camera and raise it to your eye it will slide up the strap. If there is another bumper as you describe it will be unable to do this and will make the use of it awkward as the whole strap will move when you raise the camera.
If you mean you only bring the front bumper down when you don't want it to move thats fair enough but my RS5 didn't come with a front bumper
Edit I have just looked at the video and the blackrapid site and it looks like you mean the RS Sport as that is the only one with two bumpers