Interpretation of 2822 needed

Hi folks,

Quick question on RFC2822. Sect. 3.4.1 on address formats states:

   3.4.1. Addr-spec specification

   An addr-spec is a specific Internet identifier that contains a
   locally interpreted string followed by the at-sign character ("@",
   ASCII value 64) followed by an Internet domain.  The locally
   interpreted string is either a quoted-string or a dot-atom.  If the
   string can be represented as a dot-atom (that is, it contains no
   characters other than atext characters or "." surrounded by atext
   characters), then the dot-atom form SHOULD be used and the
   quoted-string form SHOULD NOT be used. Comments and folding white
   space SHOULD NOT be used around the "@" in the addr-spec.

To me, this means that the local-part of an address may either be 
quoted or may contain dot-atoms, but may not contain embedded quoted 
substrings. For example, consider the following address local-parts:
VALID: vince.sabio
VALID: "vince sabio" (deprecated, but nonetheless valid)
NOT VALID: vince."human mail server".sabio

Is my interpretation of 3.4.1 correct, or am I reading something wrong here?

BTW, congrats all around on RFCs 2821/2!

Thanks,
Vince