Busted ...
I know you don't like me but please don't make things up and presume what I think or say or just make up what you think I might say.
I never actually said the" lightest saddle in existence is the best " Your making a presumption. "You are wrong"
Did you read the above post,
if you did then your presumption is way off ,,,,miles away. I ride a £20 saddle. How much does your saddle cost?
If your friend is using zip ties to mount his garmin and it works " that's a good idea then" What's your problem?
There are plenty of super light saddles all sorts of shapes even padded ones well under 100grms. You could pass on that information to him if he's riding around with a sore bottom. He could try TUNE. Mcfk .AX Lightness.
Smud or even get Berk to make him a custom one. There's plenty of options I think Dash and Becker make the most expensive saddles .I think one Becker saddle comes in around 40 grms. 40grms I should buy it
I'm sure he will get one that suits him.
all the best Ray J