Older STI road brifters that are losing their clicks have been responding well to forceful and generous sprays of PG2000 spray lube. The road mechanism is typically more closely shrouded than older MTB units. This has discouraged a lot of exploratory surgery. Fortunately, experimental treatments with PG2000 have yielded these positive results, giving new hope to older victims of Shimano engineering.
PG2000 treatments have brought about full recovery in RSX, 105 and older Ultegra units. We have no long-term results yet, so the patient may relapse. Still, even a bit of borrowed time is better than no time at all. A brifter with no brains doesn't even make a good fishing weight. You can at least delay the inevitable expensive replacement.