Questions about freebsd-update

[Quartz]

>>>>> The tools involved here are already part of the base system (except
>>>>> they got manually removed, which renders the OS somehow incomplete).
>>>>> A system installation typically uses compiler, assembler, linker,
>>>>> installer, and make, which are all contained in the base distribution
>>>>> of the OS.
>>>>
>>>> Wait.... isn't all the build stuff part of the 'src' option during
>>>> install?
>>>
>>> No. The "src" distribution contains the sources which will
>>> be available in the /usr/src subtree.
>>>
>>>> If you unselect that, how does make/install apply patches if
>>>> the files it's patching aren't there?
>>>
>>> It doesn't do that, but the tools make, install, and patch
>>> themselves will be available.
>>
>> I understand that the utils themselves are still installed regardless,
>> but in order for the 'patch' command to have something to patch against,
>> doesn't 'src' have to be installed also?
>
> Yes, /usr/src _has to be_ present - either by installing src.txz,
> as a result of freebsd-update's component src, or via SVN checkout.
> The process then involves building from source of course. This is
> the most transparent way to deal with updates.
>

I'm still confused here.

I was under the impression that if I ever wanted to be able to update 
the system via patches, I had to leave the 'src' option selected during 
install. Are you saying that is or is not true?