I learned this from Scott Flanders many yrs. ago, and for those of you who know him, know that he is meticulous about his race bike being race ready at all times. At both the front and rear derailleurs there are points where, if you work the shift lever can see where a part will move against another part that won't. That is the pivot point, and it makes sense to give that point just 1 drop of light weight lubricant once in a while. The rear derailleur has 4 points, and the front also 4 points. I use the smallest plastic bottle of Triflow I can find. I inserted one of those spray tubes into the top, that way I can see that I'm using just a drop. Then wipe off the any excess.