Using WLP004 Irish Ale Yeast Cake for a slightly smaller beer

Brewed O'Flannigan's stout from a recipe on the board here (1.043 OG) with WLP004 Irish ale. When I bottle it, I was going to brew the Mild Mannered Ale (1.039)

Originally, I had planned on using US-05 - but I got to thinking about just using the WLP004 cake. I've never re-used yeast before and I've read that you typically want to start with smaller beers and then work your way up - this is going slightly backwards. Does anyone see any problem with this?

I had planned on just taking a sanitized glass measuring cup and getting a good scoop of the yeast and dumping it in the new batch rather than using the entire cake. That is my understanding of the "correct" way. Anyone care to dissent? There shouldn't be much hop matter - the stout only had .6 oz of hops in it (3 gallon batch). I shouldn't need to wash the yeast or anything yet, should I?

Thanks for the input

If you don't mind carrying over a little of the stout's flavor and color, you'll be fine.

Use Mr Malty to figure out how many mL of yeast slurry you'll want to carry over. (Use the "repitching from slurry" tab)

http://www.mrmalty.com/calc/calc.html

Ah, thanks. I hadn't seen that tab on the calculator before. Thanks for the tip.

I don't think a little stout characteristic would be bad in the mild. It already has a bit of chocolate malt in it.