I really didn't know what else to say in the title... let me see if I can explain.

Dura Ace 7900 shift/brake lever (front derailleur/brake).

I noticed on my last ride that my front brake lever wasn't returning to 'zero' when released. I did what seemed logical to me (lubed the brake cable and made sure the pivot on the brake worked smoothly). Surprisingly, the brake lever still didn't return to zero without pressure.

I started looking around at the insides as much as possible and noticed some corrosion on the metal parts, so I decided to remove the entire unit to get a better look.

Upon removal, I noticed that when moving the brake lever along its action path that near the zero position it seems to catch on the downshift lever and pushes it out before snapping to zero. This is what is causing the brake lever to 'catch' and not return to neutral.

Has anyone ever seen this before? I've operated the brake lever and looked at everything I can and just don't see what is going on. Any advice would be most appreciated.

Huh... well wouldn't you know it... once I reinstalled everything it's working like a champ. Maybe it just needed a little oil and tinkering.

Or that corrsion you found was fouling things up a bit.