How should I make the best use of Code Analysis?
The best way to use Code Analysis is to diagnose a problem you have seen in your results. For example, if your email is off-center in Outlook 2013, you might find in your Code Analysis Summary for Outlook 2013 that a certain style you had been using to center the email is listed as unsupported for that client. Based on this info, you might try another technique to center the email.
Looking at each individual error in Code Analysis and trying to resolve all of them is not the intended use of Code Analysis, because many of the errors will not be relevant to your particular email. For example, you may have styles in your <head> section, which are flagged as unsupported in Gmail. This is okay, though, because those styles are included for clients that do support them. As long as you also have inline styles, you can ignore these warnings in Gmail. The warnings are there for users who don’t yet know to use inline styles, to help tip them off to why all their styles are missing in Gmail.