RESNET Explanation

Lets say there is a shortcut/ skip connection between two layers .
so a[L+2] = g(z[L+2] + a[L])
if we extract z[L+2] it will become

a[L+2] = g((w[L+2] a[L+1] + b[L+2] )+ a[L])

so if W & B here are not 0
the Skip Connection will be useless and will not improve performance ?

sorry for my bad explanation
thanks a lot

Sorry, I do not understand your explanation. Why do you feel this is useless?