use of <mark> to denote notes in quoted text

I have  been mulling over use of <mark>
http://www.w3.org/html/wg/drafts/html/master/text-level-semantics.html#the-mark-element
to
denote notes added to quoted text

example:

<blockquote>
 "That monster custom, who all sense doth eat
 Of habit's devil," <mark> not in Folio </mark>
 "What a falling off was there !
 From me, whose love was of that dignity
 That it went hand in hand even with the vow
 I made to her in marriage, and to decline
 Upon a wretch."
 </blockquote>

thoughts?

--

Regards

SteveF
HTML 5.1 <http://www.w3.org/html/wg/drafts/html/master/>