classicthesis and titlesec

Question

I'm still trying to make classicthesis work. The problem now is that I get lots of warnings about titlesec... As a matter of fact, with this preamble

\documentclass[a4paper,11pt]{scrbook}


%fonts
\usepackage{mathpazo}

\usepackage{classicthesis}  
\usepackage{arsclassica}

\usepackage{lipsum}

I get this kind of headers

I've read about incompatibility between titlesec and KOMA script, but I haven't been able to understand how to fix it. Thank you for your help.

Answer 1

I just pretend the question contains questions:

1. What is the warning concerning titlesec about?
2. Why are my headers looking horrible?

---

1) The classicthesis template uses scrreprt with the option headinclude and footinclude, which are passed over to package typearea.

Package classicthesis defines the size of the typeblock, ensuring that package typearea is loaded, but not taking into account the options passed to it. So you have to always add the options globally. Or use package geometry to change the margins, which makes using the package classicthesis pointless, as it only defines the style.

2) Opposed to it, the author of classicthesis decided to tweak the appearance of sectional headings using package titlesec, which in the meantime issues a quite prominent warning by KOMA-script, because it breaks some KOMA functionality.

You can (probably) silence the warnings, but that does not fix the fact, that classicthesis is in wide parts incompatible with KOMA-script.

---

A little example:

\documentclass[
%   headinclude,footinclude,% option for tyearea
    headings=optiontoheadandtoc
]{scrreprt}
\usepackage{blindtext}
\usepackage{classicthesis}% destroys head/toc mechanism using titlesec
\begin{document}
\pagestyle{headings}
\tableofcontents
\chapter[head={Walter Wombat}, tocentry={Gerry
Giraffe}]{Lyndon Lizard}% kicked by titlesec
\blindtext[10]
\end{document}