[Jim Bon Jovi]

true ice you don't need to know scales inside out (though it does help with the soloing) and you most definetely don't need to know useless G#485th minor 27th chords but a little know how about the composition of chords, the fretboard and chord progressions makes learning alot easier than just going about it blindly.

my best mate picked up the guitar a while back and started writing songs straight away just putting his fingers in random places he thought made good looking shaped chords (i shit you not) he was quite content doing that but never really learned anything until he started looking at some radiohead chords and tabs and started to "get" what chords go with each other, what kind of sounds they make, how to actually play them properly etc...