Got this question over the weekend:
Why can’t you just leave [the pie crust mix] in the bag to mix it with the water [and vinear]? What about if you use the 2.5 gal food bags from hefty?
…accompanied by this cryptic little aphorism/threat:
Do not meddle in the affairs of dragons…for you are crunchy and taste good with ketchup.
Taking the first part first, the reason you pour the mix out of the bag to add the liquid is that otherwise you end up moistening only the top of the mixture. That requires you to knead the dough longer, which means more gluten formation. Truth be told I have taken that short cut before and paid the consequences. However a bigger 2.5-gallon bag might well give you enough room to work so that you can distribute the water and vinegar over the whole mix.
As for the second part, what to say other than I’m pleased to know that the Society for Creative Anachronism has finally instituted a baking corps. Thanks for the email Maryann!