I had tearing problems with an injection molded TPE part. It always started creeping at the gate. When we moved the gate the problem disappeared completely, and the part was very durable (designed to replace a leather-strap). While it’s the opposite of what you’re trying to achieve, but the way it behaved makes me think your idea is feasible - if I understood it correctly. If you have the possibility to IM it, I’m sure you can tweak it to the just right by experimenting with X-cut-depth, fillets/corners, and also the main shape. I’m thinking a cone or pyramid instead of flat?