[apparmor] Working principle of alias rules

[rockit at openmailbox.org]

I have some questions for apparmor alias rules. Is it correct that an alias rule won't directly have an influence on which files can be accessed  on a certain rewritten path, i.e. the actual profile for the program is what matters more? Could you make a program less confined just by alias rules? Sure you add another path, but on this path you are still allowed to only access files as described in the original profile of the program. Is this correct?
What is the reason a rewrite path for "/" -> "/rw/" does not apply to all the rules, i.e. you have to specifically rewrite other paths too, like "/var/" -> "/rw/var/" ?