That Instruments in form of wills may be effective as deeds of conveyance is clear. If a present interest is passed and execution is complete (which includes delivery), the instrument must take effect as a deed. On the other hand, If no interest is to vest until or after death of the maker and there has been no complete execution as a deed, the instrument, if operative at all, must take effect as a will. Difficulties arise when there is a fully executed deed, which, however, is to be postponed in its complete operation until the death of the grantor.
Aigler, Ralph W. (1910-1964). "Deeds to Take Effect after Death of Grantor." Law. & Banker 12 (1919): 606-8.