Always use the tool is best practice, because it will update what is needed and use any patches or firmwares needed in the order they should be done.
The 072 firmware is for when you are going from 071-072-073. Which you are not, if you want to do the CWIS method, just do the 073 release.
Weblets are there so they can be installed if you choose to use them (The tool will ask)