I'm not sure what the ingredients are for a trueshot potion, but if people were gettting 147% increase in any potion, they were probably using a glitch of some sort. I know there is a restoration glitch that will improve the effects of your fortify alchemy gear exponentially. For instance, if you wear 4 clothing pieces with + fortify alchemy enchantments on them, and then combine small antlers with a cyrodillic spadetail, you will get a fortify restoration potion. Drink this, and you will see that your alchemy gear has buffed to a greater +alch %. Unequip your alchemy gear, then re-equip it. Make ANOTHER potion of fortify restoration, this time while your gear is already buffed, and you will make an even more powerful potion. Lather rinse and repeat. So basically, once your gear is at an alchemy level you are happy with, create your Trueshot potion, and it will be stupidly powerful ... but to be honest, this kind of exploit makes the game less fun to me.