We have 3 six houses, ie ( 6th, 8th and 12th )
The beneficial planets does not good result in these houses.
Jupiter is in the 6th house of in his sign, can will give some favorable results. It make person dull when it comes in these houses. First it gives you the result of 3rd house, the Dashaa of 3rd house does not gives
very good results, After that the Dashaa of 6th house will give results. So it will give you normal or less than normal results.
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my own experience is while Jupiter was in the 6th house retrograde mid 1998 during Shani-ketu Dashaa, I got job after a brief break; technically Jupiter is considered A-Kaarak for Tulaa Lagna, but not that bad being Lord of 3rd and 6th Houses and not lord of 8th and 12th Houses which are much bad in general.
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The planets in their own signs gives good results than other situations.
the Dashaa of 6th house is not supposed to be good for user.
Another thing, we say that For LIBRA ascendant or Lagna, Jupiter does not give good result. Because Jupiter rules two houses 3rd and 6th, and both are sick house. Another thing both are enemies.

So from Gochar point of view, you do some treatment of Raahu, you will get some good or wonderful result sure. Jupiter is in 6th house is normal. It will not give you a big loss. So enjoy.