diff --git a/lectures/preamble.tex b/lectures/preamble.tex
index 0188408..7e7346d 100644
--- a/lectures/preamble.tex
+++ b/lectures/preamble.tex
@@ -61,6 +61,7 @@
 	keywordstyle=\color{KeywordColor}\codefont\codesize,
 	commentstyle=\color{CommentColor}\commentfont\normalsize,
 	stringstyle=\color{StringColor}\codefont\codesize,
+	gobble=2,
 	aboveskip=10pt,
 	belowskip=0pt,
 	showstringspaces=false,
@@ -83,6 +84,7 @@
 	keywordstyle=\color{KeywordColor}\codefont\smallcodesize,
 	commentstyle=\color{CommentColor}\commentfont\codesize,
 	stringstyle=\color{StringColor}\codefont\smallcodesize,
+	gobble=2,
 	aboveskip=5pt,
 	belowskip=-5pt,
 	showstringspaces=false,
@@ -168,7 +170,7 @@
   {0ex}    %  indent
   {-0.1ex} %  above
   {0.1ex}  %  below
-  {\Huge\color{SectionColor}}}
+  {\huge\color{SectionColor}}}
 
 \renewcommand\subsection{\@startsection{subsection}{2} %
   {0ex}    %  indent
@@ -183,7 +185,8 @@
   {\large\color{SectionColor}}}
 \makeatother
 
-% suppress slide centering (which buggers up incremental uncovering)
+% suppress slide centering (which buggers up incremental uncovering, and makes
+% things jump around a lot)
 \centerslidesfalse
 
 % options for hyperef