Six months ago or so I reinstalled my retail COH to give it another go and the entire patching process probably ended up taking at least two hours. Not only were there a gig+ of patches, but I had to install them all one after the other. It was also hard to find them all. If I remember correctly there were something like five of them that all had to be downloaded and installed separately in the correct order.
I'm never going to do it again, and it's a shame because I probably otherwise would reinstall occasionally when I get an itch for a WW2 RTS on some random weekend. It is a good one after all. Lots of explosions and stuff.