User blog comment:Gourgeist/Shingeki no Kyojin Chapter 65 Review: Dreams and Curses/@comment-7418318-20150112232657/@comment-24930713-20150113055824

I think he said that she needed to ingest the spinal fluid. So he'd probably have to die for her to do that. I get the feeling that their medical abillities at that time aren't good enough to do what you suggest.

But I do agree with you, if they can find an alternate way. Two titan shifters would certainly be better than one on humanity's side.