I normally carry a very light pack, so I just take everything up to the summit. I don't have to return they way I came. I don't need to find the gear I left behind. If the conditions turn against me, Ihave all your gear with me.

If you carry a light pack but want to save weight for the assault? Use your pack, but leave whatever you don't need behind in a dry bag or protected by your shelter. There are some packs which have been specifically designed to carry large loads during an approach, and then shrink for summiting. Example of this sort of design are a number of packs made by HcHale Packs, and modular packs like the Kelty Cloud line.

There are a number of companies that make stuff sack / daypack combo that are light weight. Personally, I haven't found one of these that is really comfortable, but some people really seem to like them.

Use an ultralight (frameless) packs from MLD, Gossamer Gear, Montbell, Zpack, etc. They will be between 4-16oz and carry pretty comfortably.. especially if you take your sleeping pad with you.

--mark