Originally Posted by
PineFlatMike
...but I had routed my chain around that outside tab. I rode like this for quite a bit too, hope I didn't do any damage to my derailleur or chain.
About the only thing this ever damages is the mechanic's pride. Since it's on the slack side of the drive the only load is the RD cage spring, so if it's ignored for long enough, the chain might saw through the tab and solve the problem by itself, but even that doesn't matter since the tab isn't necessary.