Just did a quick check to compare Neptune Collonges with BMG.
Neptune had four goes at the Cheltenham Gold Cup, a peak RPR of 178 and peak OR of 174, later winning the GN off 157.
BMG has had two goes at the Gold Cup, a peak RPR of 174, a peak OR of 172 and gets in off 155.
Neptune won the Irish Gold Cup and two Punchestown Gold Cups.
BMG has a win and a second in the King George on his CV.
Neptune was 11 when he won the National, BMG is 'only' 10.
I think Nicholls eventually realised Neptune wasn't going to win a Gold Cup but he was unfortunate to be around at the same time as stablemates Denman and Kauto Star.
Bravemansgame is up against the best we've seen since them in Galopin Des Champs.
My suspicion is that Nicholls realises he'd be banging his head aiming for the top level again and set about getting his mark down and boy has he succeeded.
I still think the trip might be a problem but I Am Maximus won the National off 159 and has gone up to 167 so if BMG still has a 170+ in him he has to be considered very well in off 155.
Of course, there might well be other 170+ runners in the race off marks in the mid-150s and the Irish are the most likely but they aren't 50/1 
