No problem at all Orca the reason for having a laptop up there was to control another camera shooting a timelapse. A 2 stop grad ND was being used like I would normally do but the range was still too much for the camera if I exposed for the sky the cliffs were bascally black, if I exposed for the foreground I lost the sky.
Why 15 shots? purely an experiment to see if the smaller exposure increments gave a smoother colouration, which it does, but it takes longer to shoot the sequence so the clouds tend to smear. Would I do it again? probably not, but I would certainly consider shooting 5 or 7 bracketed exposures rather than a typical 3.