Before collecting data, it helps to ask whether the target accuracy is even attainable with the physics you chose. The idea: the attainable floor is set less by sample size or fitting tricks and more by which physical quantities you include and how they relate dimensionally. I’m proposing an open benchmark: share a task (H₀, α, G, heat/mass transfer, materials), the achieved relative error, and the list of variables actually used. We’ll compare empirical “plateaus” with the accuracy you would expect from the chosen description. Goal: a public map of where adding variables still helps—and where only a change of approach will.