Recipe scaling question

[Eclectic Ales]

So what are some of the things you guys have noticed that do not scale up well from pilot batches of 10 gallons to batches of 5bbl or more. I am just wondering what grains seem to be stronger than others when brewed at larger volumes.

[BrewinLou]

Most malt suppliers give general guild lines as to % use they recommend per batch on malts. Such as here...

http://www.brewingwithbriess.com/Assets/PDFs/Briess_PISB_2RowCaramelMalt40L.pdf

Hop utilization is a big factor when scaling up as each kettle's size and shape play a factor.

[Eclectic Ales]

I have looked at that site before and its great info but im looking for real life experiences from people that found out by trial and error that some grains don't scale up well.