how can you tell if you knead too much or too little.I have seen kneading times from ten to thirty minutes.Some recipes are not too clear about this .
Recipes aren't very clear because kneading can vary tremendously based on the texture you are seeking, ingredients in the dough, proof time/temps, type of mixer, mixer speed, etc. I have found it is something you need (pun intended) to play around with. Since the main purpose of kneading is to build gluten, you can often judge in the final product what changes you might want to make next time. Not enough gluten (crumbly crust) means you should try kneading longer. Too much gluten (too chewy for your tastes) means you should try kneading less. There are other factors that affect the formation of gluten (type of flour, amount of fat, amount of hydration, proofing time) which can make this a tough nut to crack (2-steps forward, 1-step back), but you just have to pick a starting point and make small moves from there.