https://sierramadreresearch.zendesk.com/hc/en-us/articles/4404429206925-Can-tightening-the-straps-damage-the-heating-elements-or-is-the-stress-only-really-applied-to-the-fabric-

https://sierramadreresearch.zendesk.com/hc/en-us/articles/4404429206925-Can-tightening-the-straps-damage-the-heating-elements-or-is-the-stress-only-really-applied-to-the-fabric-

It only applies to the fabric. So, for example, you shouldn't use the fabric if it's torn or if the heating element is exposed.