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Message-ID:  <4E7A1579.1000009@morningstar2.co.uk>
Date:         Wed, 21 Sep 2011 17:48:57 +0100
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From: Joseph Wright <joseph.wright@MORNINGSTAR2.CO.UK>
Subject: Re: \interlinepenalties
To: LATEX-L@listserv.uni-heidelberg.de
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Status: R

On 21/09/2011 17:34, Bruno Le Floch wrote:
> Context uses it in \keeplinestogether, but I don't see why they
> couldn't have used \clubpenalties instead. I don't understand the
> difference between \interlinepenalties and \clubpenalties as described
> in etex_man:
> 
> - the ith interline penalty value is used after line i of the paragraph;
> - the ith club penalty value is used after line i of a partial paragraph;

My reading of this was that the variation comes down to whether there is
any display math about, but in such a case I'm doubtful you'd want to
'keep together' in any case. As you say, in most realistic circumstances
\clubpenalties seems to be quite usable, as you have to start from line
1 with \interlinepenalties too.
-- 
Joseph Wright