A lot of people tend to over-tighten their straps. If you have a strap rated for 10K that you crank down so it has a static load of 8K then you only have 2K left for any shock loads. The whole beauty of nylon straps is their ability to stretch under load but if you tighten them "bar' tight, like a chain binder then you are overloading them. If they are the right size for the load you just have to have them snug to hold the load in place.
