All my mini tools have a chain break. I've never once needed a chain break on a ride in 20ish years. Its not there to help repair my chain, it's there to alleviate the irrational anxiety I feel if I don't have a chain break. It works!
This is all in good humor...
Unless I'm on a remote bike tour far from civilization I'm giving the chain tool a big middle finger! Now watch my chain break on the next ride. I refuse to buckle to "Chain Anxiety", until I don't, of course

. But still, I won't carry one on "around town" rides that don't venture more than 20 miles out of town.
I used to carry all kinds of stuff in a bag on my bike, even a spare brake cable! I mean, who does that??

There was a reason to carry that brake cable though but it wasn't a good one.
As I stated before I do carry a multi-tool on one bike and it's a fixed gear. I don't ride it often but it
deserves a good multi-tool! Will I ever have to use that multi-tool? Probably not but if I do get into a bind my guess is I'll be thanking myself for having the multi-tool,
with a chainbreaker, to save the day!.
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