This does help! I have mine mounted like that and I never have a problem. However I do have a few thousand sets in stock as a back up just in case!!
Seriously though....mounting them on top of the rail does help. In addition to the traditional spring style I am hoping to release a reversible (spring style) unit very soon. Still prototyping but looking good!!
Oh.....and if you do buy a set of mine and bend or break one (even if you back up on it) I will replace for up to three months after your purchase at no charge providing you pay shipping or arrange shipping.