this has been my procedure from the start but this thread brings up 2 questions:
1. are you worried about having left wallet "fingerprints" on your pc that could be reconstructed and stolen?
2. have u tried to store the entire data directory on the usb stick thus allowing u to not move the wallet to your pc? i have recently tried this and encountered 2 problems
a. its enormously slow to download the block chain and it appears u can't just drag a full block chain from one folder to another to avoid the ful download.
b. sometimes it works and sometimes it doesn't in terms of the client being able to detect this usb data folder.