Originally Posted by Wordbiker

Pretty much all modern chains are not meant to be broken and pressed together again.

Shimano has their proprietary pins, other manufacturers use various master links, but all of them are an attempt to keep the peened pins on the chain intact. Break the chain once to size it, apply the master link or pin and that's it. If the chain breaks, needs to be resized or wears out, you buy a new one and start over...or add another master link or pin.

I do miss the old days of being able to break a chain and reinstall it, but considering it's about $15 to replace a chain, that's cheaper than destroying a rear derailleur or the medical bills for a chainring peircing.

Don't doubt your skills man. I'm sure you did a good job...the chains are just designed for planned obsolescence.