This devotion I only came across very recently and has similarities to The 15 prayers Jesus gave to Saint Bridget of Sweden. http://www.catholictradition.org/Christ/holy-wounds2.htm It gives the following 5 graces. (See the 5th one, thats some promise for just 2 Our Fathers, 2 Hail Marys and 2 Glory Bes x 3 years) 1st: The plenary indulgence and remittance of your sins. 2nd: You will be free from the pains of Purgatory. 3rd: If you should die before completing the said 3 years, for you it will be the same as if you had completed them. 4th: It will be upon your death the same as if you had shed all your blood for the Holy Faith. 5th: I will descend from Heaven to take your soul and that of your relatives, until the fourth generation.
