stack. what is it? why are we so rubbish at what it is? 

If you have a bathroom scale and a 3/4" wooden stick you can in principle measure any draw curve. As precise as your scale and inch tick marks mind you, but it is not out of reach for a common household.

@@mozu305 stack isn't a muscle thing. It's a geometric thing. We can deliver 2lb gain. 1lb gain and 0 lbs gained over 5" of draw. Amd each one is smoother than the pther

@@BorderArcheryLTD what the poster was trying to say is that at anchor in Oly the leverage ratio is poor, the large muscles are pretty much at maximal contraction and every second held there cause FATIGUE , repetition of the cycle causes extreme fatigue and lactate build up . The actual expansion of 2mm may be tiny BUT it is at a point where the musculo skeletal system has little left to give especially if trying to maintain form . Thus the proprioception of stack becomes very sensitive . I can tell the difference between Hex 5/6/7/CV2 and CV5 eyes closed. I totally agree with your explanations and engineering concepts/definitions but to dismiss the last 2mm as being neither here nor there because the increase in # is small isn't helpful as it ignores mechanical disadvantage of the human system at expansion especially when trying to expand carefully to maintain sight locking and also increase to "push" in the bow arm to counter the draw. For me then a 0 # increase over the last 0.5" would be best if the limb technology is torsionally stable enough for Oly recurve .

@@mikebyford5258 so your saying you can feel the difference of 0.3lbs over 1" when your only looking at 2mm out of the 24mm the 0.3lbs I talk about is tue difference between a smooth model vs a less smooth. Aka. 0.025lb.over 40lbs. And this is something you base your anchor off?

@@mikebyford5258 I would put down the feeling of 11g of difference between a smooth bow and a stacky bow in those 2mm of expansion is more a legacy feeling. A bit like not knowing somethings heavy and it defeats you with the supprise. Opposed to knowing somethings heavy and fully committing to it, and your impressed with your efforts.

@@BorderArcheryLTD I think your hypothesis has two mistakes: 1. it is logical and 2. sensible. I don't disagree with your analysis and how it can quantify a draw force curve at all. However, that was not my point. I think why the concept of stack is prevalent is that it is a perceptual quality and totally subjective. As you said, depending on what limbs you have been shooting, the next pair could be really "smooth" or "stack" simply because the draw curve is different from what the archer had become used to. I would further add, I suspect that draw weight has nothing to do with the perception, even though heavier limbs that are described as "smooth" may increase poundage at a greater rate than lighter limbs that are perceived to "stack." And as you say, how anyone can tell the draw weight increase in the small movement an archer has at anchor to execute a shot does not seem plausible. Because of the subjective nature of smooth/stack, I doubt it is going to leave archery vocabulary as those are really expressions of a feeling.