Expectation:
"Chain" command blocks will only trigger if the first command block successfully executed a command.

Result:
"Chain" command blocks will trigger as long as the first command block is powered regardless of whether the first command block successfully executed a command (even if the command block is blank).

Steps to reproduce:
1) set down a blank command block on impulse mode
2) set down as many command blocks on chain mode as desired so long as they point into each other like in the picture.
3) type different "/say" commands into the "Chain" command blocks to determine if they are being triggered.
4) Power all of the "Chain" command blocks.
5) Power the blank "Impulse" command block