The trackpad on my wife's mid 09 MBP was not recognizing the physical click, for almost two years. The optical drive was also not functioning for over a year. We have three kids and they sometimes move faster than we can take things away from them.
Due to the step by step guides the repair was easy peasy. It went just like the guides said.
The only surprise was the torque screw under the trackpad. There was no mention of this in the guide and the trackpad came with a new one (didn't use). Because it seemed to be just a screw and the new trackpad worked fine with the old screw, I just left the old one in there.
Unibody 8x SATA SuperDrive (Post-Early 2009)
MacBook Pro 13" Unibody (Mid 2009 - Mid 2012) Trackpad