That is true. If the dollar collapses and they try to fix things by hyperinflating, or devaluing the dollar, then yes, holding cash is the last thing you want. However, I think that point is still a ways off. For one thing, Japan and now Europe are back in crisis mode, and China may not be too far behind. We are looking good by comparison, and so there are a lot of people around the world who will be trying to put money here. They are already buying up our real estate, Japanese companies are buying assets here, they are buying are markets. This makes the dollar more valuable. Gold should not be doing well right now, at least in dollars. Gold priced in Euros might skyrocket, but not in dollars.
Right now dollars are king, until Europe, Japan, and China fall, and they are at the bottom. Then we will fall last, and the dollar goes with it. In the meantime, by having valuable dollars, you will be able to buy other assets cheap, because they are falling against the dollar
I'm not predicting an imminent collapse, either, but the facts you mention, though they do make the dollar more valuable on foreign exchange markets, do not translate directly into increased purchasing power at home.
The higher value abroad is a very mixed blessing. It does bring investment [good], but it does encourage more importing of foreign goods, too [not good when it's caused by money manipulation]. Ugly times we're in, methinks.