Sorry Pace, bit of mind drift on my part. I was talking about your common or garden Cu, not Cb.
I've heard glider pilots talk about cloud climbs (done them myself, although I wouldn't now unless I was getting some kind of service from an ATC unit) and there seems to be a general opinion that any power stuff will be clear of cloud which isn't true. If I'm IFR I don't route around Cu if I'm climbing or descending, there wouldn't be much point being IFR would there.
Having said that I will always be on top of them if possible.