Problema de espaço Titlesec

Question

\documentclass[11pt,]{article}
\usepackage{titlesec}
\titleformat{\section}[leftmargin]{\normalfont
\titlerule*[.6em]{\bfseries.}%
\vspace{6pt}%
\sffamily\bfseries\filleft}
{\thesection}{.5em}{}
\titlespacing{\section}
{8pc}{1.5ex plus .1ex minus .2ex}{1pc}
\begin{document}

\section{This is a section heading}
\begin{enumerate}
\item This is the first item and it is too low on the page...
\item This is another item
\item This is another item
\item This is another item
\item This is another item
\item This is another item
\item This is another item
\end{enumerate}
\section{This is a section heading}

This paragraph is fine ...
\end{document}

Por que estou obtendo espaço vertical extra antes de uma lista, mas não antes de um parágrafo?

Answer 1

Basta adicionar este código entre \section{…}e sua listasem adicionar linhas em branco:

...
\section{This is a section heading}
\leavevmode\vspace*{-\dimexpr\baselineskip+\topsep\relax}
\begin{enumerate}
...