You are mixing up 2 things, Saudi Arabias social programs being funded by oil, and actual oil productions costs which can EASILY survive $40-50 oil
"however shale cannot pick up a huge amount of slack as it simply does not have the infrastructure/resources to."
Disagree entirely. Where do you think all those rigs have gone? and how many wells are "shut in" waiting for more economic times....(like your $60) min.
Large conventional discoveries take years/ FID years, but shale can be turned on like a tap, and the infrastructure/ equipment to do so is a plenty. Even a new well can be drilled/fractured and hooked up within a month in many US shale hot spots.
"I'd bet my last dollar on the belief oil will be closer to $60 within 12 months time."
I don't disagree that is possible, but I wouldn't be putting my last $1 on it.