Since I wasnt able to find my modern soldering station I have used this old timey heavy duty one:
Here I have three ribbons. The one at the bottom I have played around with quite a bit to get the feel for it. The middle I have applied 1-2s light touch in the middle as well as 2 points to the left and 2 points to the right. The top one is untouched. The deformation of the flex is due to me taping them onto epoxy:
Here I did apply 20s in the middle:
Here another 20s on the some COF:
Superficially they seem to be quite resilient. When I'll do this on the TV I will stick to 1-2s and a light touch. I will have a metronome running at 240bpm to ensure the timing is right.