Out on my roadie today I had a bit of a chain based fail.
While out of the saddle on a pretty steep hill my chain just decided to snap on me. I was in a pretty low gear and wasn't shifting.

Where it snapped (the link had just bent open) was where I'd last broke the chain to take it off the bike for a good clean. It's a 10 speed SRAM PC1090R (or something like that) with one of they're powerlinks that don't come undone again (standard on 10 speed for some reason).
When you break the chains are you meant to do something to stop them snapping? I didn't realise this would make it so weak!

I'd suggest if you want to remove a chain regularly for cleaning, do it at the powerlink, rather than a random link in between. Some chains need new pins to rejoin them if they are broken (older shimano spring to mind), some chains need specific tools to break & reconnect (campag 10 spd IIRC).

Bit surprised that you can tell it was where you'd last split it, my chain has 100 odd links or so, and without sounding racist they all look the same to me!

am I right thinking you broke the chain and then used a powerlink to reconnect it, and it is the powerlink that has broken? You cannot (well, should not) reconnect a 10spd chain using a normal link, that will probably break.

If the powerlink broke, it's a problem with the powerlink!

I guess chains do break occasionally, we have to live with that.