Don't tell me
is a bad idea. I just cut the rails where the rear fender bolts are attached.
As you may notice, the material is VERY hard, so there is no issue with
the bags' weight. The piece of metal is string enough to hold the bags
with the maximum load. Also the part of the guard that attach to the passenger
footrest plate will remain intact.
In the event of a flip of the bike to any side
(it may happen), the push force will be against the lower part of the cut,
and it is strong enough to hold in place without hesitation. I did a test
myself and it worked very good.