Try it with version 0014.
the blink example referred to above is no bigger if importing but not using the LiquidCrystal library.
Adding the constructor brings in 400 bytes of library code.
Adding a println statement adds 54 bytes but adding a second println only adds another 16 bytes. I think that shows that there is a difference in code size with unused functions.
it's not the number of lines that correlate to code size, its the actual number of bytes of machine code that the compiler produces for each function.