A really stupid idea, IMHO. I mean one of the principal functions of a crank bolt is to tighten the cranks, and alloy bolts could not do so without a high risk of failure.
Uh, if you'd bothered to read the instructions prior to installing, you'd have discovered that you first install the crank arms with *steel* bolts, then remove them and replace w the nifty aluminum ones... It's that "bling factor" ya kno, sorta like "Built for Speed" decals on some bikes. Very stylin'
Nor Meyer, holed up in icey Mt. Vernon, IA