@Chopsicle clearly has more experience that i do, but I thought I'd just describe two experiences I've had with 5+ years old stuff.
Before you start doing this it's worth considering whether the Gore-Tex is actually still intact.
Despite it "never wearing out" the membranes do wear out especially if run through a high heat dryer and abused with improper care. Especially on the 2 layer stuff.
I've seen cases where speckles of light start shining through 2-layer stuff after years of abuse and I started to see the membrane wearing off from the inside.
I'm not saying to go and throw it out or not try to repair it. This has just been my experience on a 2-layer Rapha jacket and old pair of North face ski bibs. Try as you see fit to fix the seam... but it might be in a death rattle if it's an especially old garment.
@Chopsicle clearly has more experience that i do, but I thought I'd just describe two experiences I've had with 5+ years old stuff.
Before you start doing this it's worth considering whether the Gore-Tex is actually still intact.
Despite it "never wearing out" the membranes do wear out especially if run through a high heat dryer and abused with improper care. Especially on the 2 layer stuff.
I've seen cases where speckles of light start shining through 2-layer stuff after years of abuse and I started to see the membrane wearing off from the inside.
I'm not saying to go and throw it out or not try to repair it. This has just been my experience on a 2-layer Rapha jacket and old pair of North face ski bibs. Try as you see fit to fix the seam... but it might be in a death rattle if it's an especially old garment.