But either way, if the engagement point for a proposed tipping point is now presumed to be lower than it might have been previously in our geologic history then I'd expect that change to be described and quantified in the literature.
It's an inherent aspect of any climate model. All of these models and forecasts are taking our current, compounding influence, into account. The uptake of carbon sinks, non-linear relationships between CO2 and temperature increase, the effects of human land use on the production/release of other greenhouse gasses, etc...the current state of all these has to be worked into any future prediction, and are. Applying the same metrics to a different baseline wouldn't work any more than treating compound interest as simple interest in figuring how much stock will be worth in 20 years.
The sort of explicit statement you seem to be looking for will be hard to find because it seems like a given that is implicit in the fundamental nature of any sort of forecasting. Change the starting variables, change any variables, change the outcome. Almost any paper talking about any kind of tipping-point or uncertanties in predictions should make this clear.
You could probably use educational modeling software like
EdGCM (download links are all broken, but I'll see if I can find some working one) to see for yourself. It's still fundamentally modern enough to be used as a benchmark for newer models, but simple enough to run on personal computers. Been a while since I toyed with it, but I'm certain you can adjust variables independently to see how they interact. Might be worth plugging in figures for some arbitrary time in the past, leaving out the human stuff, offsetting the temperature and letting it run. May well be newer software out there as well, but that's what came to mind.
So on reflection the poles have always shifted (this cause the earth to wobble on its axis) and the climate has always been changeable.
The shifting of the poles has increased recently around the same time the climate has become more erratic/extreme and some of you believe this is just a coincidence and it's not a factor, OK.
I think you are confusing geomagnetic shift with apsidal precession.
We aren't talking about the Earth wobbling on it's axis. Those patterns are well known, extremely predictable, and already well accounted for in any climate model.
The geomagnetic shifts (excursions or outright reversals) do not appreciably change the way the Earth wobbles. They disrupt and occasionally reverse the magnetic poles, not the physical ones.