I think we can all agree that BA makes it possible to attain over the max xp rate of just doing agility by itself (72k). Therefore, the max xp rate with BA (whatever it may be) should be used in the 200m all skills calculator despite the fact that some may view it psychologically impossible to do over a long period of time. The most accurate way to represent exactly how far closer to 200m everything player x is in comparison to player y is to use the maximum known xp rates, whether psychologically plausible or not. Because of these human factors such as sacrificing optimal xp gains in return for a more pleasureable training method, these theoretical "hours left" are not by any means the exact number of hours that the player will in reality will take to max out. However, since we can not numerically calculate to what percent of maximum efficiency each individual player will train at, the only fair and accurate way to represent the progress of the account in comparison to another is to use the maximum xp rates. Basically because of the variety of different playstyles there are, the purpose of using these optimal xp rates is to compare the progress of player's accounts themselves, not the playstyles or training preferences that the actual person uses. Yes, there is the possibility that no one may ever use a horn for 200m xp. This however is irrelevant when comparing account progress because despite how impractical the method might seem, the xp rates are still there and will continue to be there unless Jagex removes BA. You cannot rule out the mathematical possibility of an xp rate just because the vast majority of players would prefer not to do it. Making mathematical exceptions in a calculator for psychological or normative reasons only makes the calculator less accurate when comparing the progress of a specific account to another. When you make an exception to the calculator and deny a mathematical figure that is clearly possible to attain, even if 99.9999% of the rs population refuses to train it that way, it only makes room for more exceptions for non-mathematical reasons such as "oh training using this method would make my hand fall off, let's input the xp rate of a sub-optimal method that's easier to do" which only makes the calculator less and less accurate when comparing the progress of the account itself. You really just can't make these types of exceptions for this type of calculator even if one speaks for the vast majority of the population.