important rule from Bhavarth Ratnakar : Presented By Sri Sanjeev Ranjan Mishra FB Pg Astrological Researches..

An important rule from Bhavarth Ratnakar – a great compilation from Ramanujacharya :

If the lord of 9th is in the 8th, his dasa will not confer any fame, but if Jupiter as lord of ninth is placed in 8th the person becomes highly fortunate.
Generally you know that any planet in 8th or 12th from any house is not good as both are trik house. But Jupiter is exception to this general law – this works in practice. Remember this law is for dasa-- any law do not contradict the basic rulejust modifies it.

one can extend the rule for other houses also -- to illustrate one born in capricorn ascendent and jupiter is placed in 11th house - the person will get good result in relation to 4th house in jupiter dasa.