Mich. Comp. Laws § 566.104: Conveyance by person authorized to revoke grant; validity.

Sec. 4.

When a power to revoke a conveyance of any lands, or the rents and profits thereof, and to re-convey the same, shall be given to any person, other than the grantor in such conveyance, and such person shall thereafter convey the same lands, rents or profits, to a purchaser for a valuable consideration, such subsequent conveyance shall be valid, in the same manner, and to the same extent, as if the power of revocation were recited therein, and the intent to revoke the former conveyance expressly declared.