Memorizing the fretboard can even be easier then that; one big block though is that people learn the bar chords with root on the 6th and 5th string ( which is great so far because you learn the notes on the 6th, 5th and 1st string already ) but most of the beginners skip the bar chords with root on the 4th string ( basically open D form with a bar 2 frets lower and very usefull for playing triads in funk and other styles ), learn them and then for the G string all the notes are the same as the A string but 2 frets lower and for the B string 2 frets higher then the A string, that's all there is to it.

Herman