Rebbe as Moshiach section historicly innacurate
"During these appearances his followers would chant, what would come to be a very controversial "mantra" among the Lubavitchers  Yechi Adonenu Moreinu v'Rabbeinu Melech Hamoshiach l'olam voed! - "Long live our Master our Teacher and our Rabbi King Messiah forever and ever!" When sung before him in has last months, Schneerson evidently vigorously encouraged the singing by swaying to and fro and swinging his hand, as he had done at the numerous farbrengens over the years. From this and his previous public statements his followers "extrapolated" that he acceded to their wish that he be the "Messiah". But that moment never arrived, as he died unable to verbalize and say anything to confirm his followers' longed-for dream that he be the actual long-promised Jewish Messiah.
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1)The Rebbe encouraged public singing of Yechi Adonenu Moreinu v'Rabbeinu Melech Hamoshiach l'olam voed! - "Long live our Master our Teacher and our Rabbi King Messiah forever and ever!" as early as 15th of Yiar 5751 (29th of April 1991) almost a year before his 1st stroke see this video clip for example: http://video.moshiach.ru/events/first-yechi.rm in it you can clearly see Chassidim singing Yechi and the Rebbe encouraging them in Yidish to sing it once more.
beyond that look at this clip again before the Rebbe's stroke Mrs Chavah Cohen is giving the Rebbe tambourine with "Yechi" writen on it the Rebbe gives her a blessing http://video.moshiach.ru/events/yechi-tambourine.rm