If I understand it correctly, P4 does offer a way to handle editorial
material inside elements rather than as attribute values.  Rather than
using <sic> and <corr>, why not use <del>?  Any corrections to the
deleted material may still be indicated by <corr>, e.g.,

      <del>The stuff to be <corr sic="delted">deleted</corr></del>

Where there is an authorial deletion and then addition to the text, the
<del> and <add> pair may be left as a sequence, e.g.,

      <del>I deleted this</del> <add>and wrote this</add>

or wrapped in a <seg> element in order to simulate P5's <choice>
element.

   <seg type="choice">
      <del>The Wrong <reg orig="Stuf">Stuff</reg></del>
      <del>The Wright Stuff</del>
      <add>The Right Stuff</add>
   </seg>

Since seg may contain add, addSpan, del, delSpan, sic, corr, etc.,
marked up phrase-level textual alternatives aren't a problem.  Even
alternatives to the alternatives can be included since <seg> may contain
itself.

--
Perry Roland
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