chas, its easy on a guitar to transpose chords, just play a bar chord, and all you have to do is slide up or down the correct number of frets(each fret= 1 semitone) with the chord shape remaining the same...although to be fair, transposing open chords and melodies probably has the same degree of difficulty as the keyboard..
dennis..
PS on the subject of technique/feeling i remember an academy awards night many years ago and the entertainment came and went, big production numbers, performers with flashing lights and the whole nine yards, and then sammy davis jnr came on with just a pianist and himself and a single spotlight, i forget the tune now, might have been something from sweet charity or similar,BUT he absolutely brought the house down with that simple, but heartfelt performance...standing ovation that lasted about 5 minutes...to me that was a pure example of "feeling" a song as against "playing" a song....dunno if that story is relevant, but i thought id put it out there anyway..
cya
dennis