[jc24]

I am planning to brew a Foreign Extra Stout and want to add 1.7oz medium toast French Oak cubes (6.3 gallon batch). In order to try and minimise oxidisation and risk of infection, I'd love to avoid transferring to a secondary fermenter. What are the draw-backs to adding the oak cubes at the very start of fermentation, ie. when I pitch the yeast, and just leaving it for 3 or 4 weeks? I know that, theoretically, there is risk of off-flavours developing from the trub, but I'm not convinced :-) Anyone had real-world experience that can advise?

[mainebrewer]

I think that leaving the oak chips in for 3-4 weeks would give you a very very strong oak flavor.
I don't kthat 3-4 weeks on the yeast is going to be a problem as far a developing off flavors.
If I were going to add oak to the primary, I'd wait until the last part of the primary fermentation process.
Also, the beer should be all done well before 3-4 weeks.