Cleanly and Selectively Subdivide a Mesh.

Hi. Been doing Blender for about 2 months now and start to get results I expect to see.
I’m doing product design, particularly water containers at the moment.

I have been using ONLY LoopCut&Slide, because that’s the only way I know how to add more detail to model. Unfortunately after certain point, LoopCuts create tighy and ugly artifacts to Subdivision Surice Modifier. I spend lots of time cleaning up the junk LoopCut&Slide has created on the ‘other side’ and rather find a way to more effectively split single of multiple faces.

I am looking for a way to cleanly and selectively subdivide a mesh.

I googled up something called KNIFE (KS) Shift+K, but it does not respond on my 2.60a.

Im sure there is a super simple way to do what im looking for.