# Vertical alignment in sections beginning with itemize

I'm working on a résumé which places section headers in a widened left margin. In the example below, I am trying to get the itemize in section Bar to be vertically aligned with the section title, much like the content is aligned in the other two sections. However, there is an undesirable gap before an itemize which begins a section, despite several settings which aim to prevent this (e.g., topsep=0pt).

What am I missing to "consume" this space and bring the itemize up? I've tried negative \vspace and \vskip, but that's a hack at best, and is prone to much trial-and-error. (Relatedly, are some of my \setlist options unnecessary for this?)

\documentclass[10pt]{article}
\usepackage[utf8]{inputenc}
\usepackage[margin=0.75in, left=1.5in]{geometry}

% https://tex.stackexchange.com/a/1315/10906
\usepackage{titlesec}
\titleformat{\section}[leftmargin]
{\sffamily}
{}{0pt}{}
\titlespacing{\section}
{4pc}{1.5ex plus .1ex minus .2ex}{2pc}

\setlength\parindent{0pt}
\usepackage{enumitem}
\setlist{nolistsep, nosep, topsep=0pt}
\setlength{\parskip}{0.5ex}

\begin{document}

\section{Education}
\textbf{Metasyntactic University \dotfill Date}
\begin{itemize}
\item Degree 1
\item Certificate 2
\end{itemize}

\section{Foo}
This is some brief free-form text about some stuff that I can do.  Did you know I do Thing~3 and Thing~4?  It's pretty cool; I know.

\section{Bar}
\begin{itemize}
\item Skill 5
\item Skill 6
\end{itemize}

\end{document}


Correct this behaviour manually by vertically skipping back to the same baseline:

\documentclass[10pt]{article}
\usepackage[margin=0.75in, left=1.5in]{geometry}

% http://tex.stackexchange.com/a/1315/10906
\usepackage{titlesec}
\titleformat{\section}[leftmargin]
{\sffamily}
{}{0pt}{}
\titlespacing{\section}
{4pc}{1.5ex plus .1ex minus .2ex}{2pc}

\setlength\parindent{0pt}
\usepackage{enumitem}
\setlist{nolistsep, nosep, topsep=0pt}
\setlength{\parskip}{0.5ex}

\begin{document}

\section{Education}
\textbf{Metasyntactic University \dotfill Date}
\begin{itemize}
\item Degree 1
\item Certificate 2
\end{itemize}

\section{Foo}
This is some brief free-form text about some stuff that I can do.  Did you know I do Thing~3 and Thing~4?  It's pretty cool; I know.

\section{Bar}
\leavevmode% Start paragraph
\par% End paragraph/enter vertical mode
\vspace{\dimexpr-\baselineskip-\parskip}% Vertically jump back to baseline of section
\begin{itemize}
\item Skill 5
\item Skill 6
\end{itemize}

\end{document}