That could work, but I'm not sure if I could do that. It's more likely I would create an excel sheet with the exact amounts and then try to find a recipe size which gives somewhat reasonable amount for all the ingredients. I'm trying to avoid too big rounding up or down, as I'm worried it might harm the end result.
However, how would I know, if I have never tasted anything with the real recipe? :)
In my experience recipes are approximate anyway, and the exact amounts will vary according to difference in ingredients, brand of butter, individual ovens, etc. Amounts given are guidelines, and you have to experiment to refine them into something that works best for your own conditions.
You're completely right. Even something as simple as flour affects baking a lot - older flour is typically drier than fresher flour is. This can lead into very different results in the end if you just try to follow everything using exact amounts.