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Message: <blockquote data-quote="tomedunn" data-source="post: 9420636" data-attributes="member: 7040979">Not to undercut your point too much, because I do think DPR can be useful for comparing class features, but I'd like to offer up an example of where even this can go wrong, using Great Weapon Master vs a +2 to Strength as an exampleLet's say we have a PC with 30 hit points, who wields a standard greatsword (2d6) with +3 Strength modifier and a +5 to hit, and for some reason they only have 13 AC. They're about to face a monster who also has 30 hit points, wields a standard battleaxe (1d8) with a +4 Strength modifier and a +6 to hit, and who also has only 13 AC for some reason. For simplicity, lets assume the monster goes second in the initiative order.If we calculate the average damage for each, the PC deals 6.85 DPR against monster, and the monster deals 6.175 DPR to the PC. If we run the numbers based on just that, we find the PC has a 66% chance of winning.Now, lets look at the case where the PC has the option to take either a +2 to their Strength score or a feat that gives them a power attack for -5 to hit and +10 to damage (think Great Weapon Master but without the bonus action attack on crits).If the PC takes the +2 to Strength, their Strength modifier goes to +4 and their attack bonus goes to +6, and their average DPR increases to 8.05. And, if they take the power attack feature, their attack bonus goes to +0 and their damage modifier increases to +13, giving them an average DPR of 8.35.Clearly, 8.35 DPR from the power attack is higher than 8.05 DPR from the Strength increase, so that must be the better choice. Right?Well, no.If we run the numbers on the encounter again, their chance of winning with the power attack is 71%. That's a nice improvement over their initial chance of winning of 66%, but how does it compare to the +2 Strength option? Turns out, its 6% lower. Running the numbers on the +2 Strength build results in a chance to win of 77%! It's not just better, it's quite a bit better. How is that possible?The reason is pretty simple. While the average is slightly higher for the power attack over the Strength improvement, the standard deviation is significantly worse (10.5 compared to 5.9 for the Strength improvement). In other words, the results are more variable for the PC who took the power attack option. When the inputs for an encounter are more variable, unlikely outcomes become more likely. And, since this encounter already favored the PC, that means the odds of the monster winning were bound to increase.DPR can be useful, but it can sometimes be misleading. Similarly, average outcomes can be useful, but they also can sometimes be misleading, especially when large differences in variability are concerned. Control spells are great, but they often carry with them high levels of variability that needs to be accounted for.</blockquote>

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