I dont know how this will work, but

Im planing on brewing a wee heavy and a sweet potatoe scotch 60/- I dont know how well this will work but my plan is to use two mash tuns bolth with
15lbs of 2row
.5lbs biscuit
1lb munich
.75 lbs special b
.25 lbs chocolate
collect runnings from bolth mash tuns to 7.5 gallons for the wee heavy
then add a lb or 2 of 2row and 2.5lbs of mashed & whipped sweet potatoe to each mash and collect 2nd runnings for the second beer.

any ideas?

Never heard of a Scotch ale using Sweet Potatoes.
Why would you want to do it and is it still a Wee Heavy.
Good luck.

As a caveat you need to know that I think you should drink beer and eat food and not put both in the same container unless it's your belly.

my plan is for 2 beers, collecting the 1st runnings from bolth mash tuns for the wee heavy and collecting the 2nd runnings for the sweet potatoe beer.
Im thinking the 2nd runnings will be close to a 60 /- scotch ale. Im trying to brew a beer for thanksgiving and I got the idea from a recipe for sweet potatoe esb in brew magazine.
I have been having efficiency problems so my origional idea for the wee heavy was just a 2 mash tun brew with a mash out, almost a no sparge beer. then I started thinking why not collect the second runnings for a smaller beer.
is this worth trying?

I'm thinking of doing something similar for a barleywine or imperial stout. It seems like it would work. I am just concerned about the amount of time it will require. It is probably easier to make up the gravity difference with DME for your wee heavy but if you have the time I can see why not.
Craig

But Orfy, aren't grains food?

Sounds like a great idea, and probably very close to the traditional process for making beer. I wonder how much sugar the sweet potatoes will add...