I started DB when I was 15, having been booted out of 'cello lessons for not practicing. My teacher had studied with Gary Karr and she advocated 1234 all over the fingerboard. I knew no different and went with it. I got some pretty funny looks when I ventured beyond my county music system and encountered other tutors. They were pretty derogatory about what my left hand was doing but my hands are big and intonation has never been an issue, even though the beginning of the really slow variation in Enigma was an adventure I have had students with not as much span and they have indulged in the closed hand thing lower down and then gone extended as they moved up the neck. The real answer is whatever works for you. The DB as we know it is a relatively young instrument and there are all sorts of ways of playing it. If you can do 1234 then by all means do so. It opens things up for a lot less moving around.