Shaykh Ahmad ibn Idris was asked: “What is al-salaat al-batraa’ (The Cut-Off Salaat)”?
He said: To invoke blessings upon him (may God’s peace and blessings be upon him and his family) without his family, because this removes from it the baraka (extra blessings). This is because when one invokes one blessing upon him, Allah blesses the person ten times in return (as narrated by imam Muslim and others). This is the same with his family: ten blessings come back to him from each one of them, no matter how great in number they reach. “But among you are those who are niggardly, and whoever is niggardly is niggardly against his own soul” (Q 47:38).
Shaykh Salih al-Ja’fari was asked: “What is meant by al-salaat al-batraa’ (The Cut-Off Salaat) ?”
He said: It is the one in which no blessing is sent on the family of Prophet (may God’s peace and blessings be upon him and his family).
I was once writing a book, and the scribe was too lazy to write “and upon his family”. When the scribe slept, he saw our master al-Husayn (may Allah be pleased with him) holding out to him an apple and saying to him: “Say: ‘and upon his family’ so that I would give you the apple.”