I wish to acknowledge that I did read Z's question, which is about using GCEA strings in some form to create a DGBE tuning. I do not have answers to that. But I do have some links to information about the notion of tuning a tenor ukulele to DGBE at all. Also, Dirk's post on the thread (linked below) somewhat answers the original question about strings sizes.
Two things: This is a video from Gordon at Mya Moe about baritones tuned like tenors (not your question), but wait! At 4:40 minutes, he gives an opinion about tenor scales tuned to baritone--please advance to that part of this video:
http://www.youtube.com/watch?v=7WDRq5qsBsA
And second, a past thread with your question with many good answers, one of which is from the experience of Dirk, at Southcoast Strings (who basically agrees with Gordon), and from Kissing, who has tried amplification successfully.
http://forum.ukuleleunderground.com...cale)-baritone&highlight=tenor+tuned+baritone
I think if tuning a tenor-bodied ukulele to DGBE worked well, with any strings, most of us would be doing it on one of our tenors (rather than buying a baritone uke and getting adjusted to yet another fret scale size). I know I would do it (only if it worked well).
Good question, Zakulele. Of course, if I am not wrong, since your are tuning down and not up, you could simply try your idea of GCEA strings, in the pattern you suggested, on a tenor-necked instrument and tune down to DGBE with little repercussions; if you did so, you'd be able to answer your own question and certainly then be the most knowledgeable here on this subject.
Best of luck on your cigar box ukulele.