When planets eventhough located in their own signs or friendly signs or exaltation signs cannot yield full benefic results when enemy planets are located either behind or next to them and they remain neutral being unable to do either good or bad.
When a benefic planet is hemmed in between two enemy planets, there will be impediments to the benefic effect of benefic planet.
When an enemy planet located in 2nd sign to the sign where a planet located is retrograde, the planet in the first sign gets affected and yields malefic results.
A planet cannot yield its results if there are no planets located in the 7th, 2nd, 12th and 5th signs therefrom. Even if it yields its effects will be most minimum. But this planet if it gets planetary interchange with some other planet can work wonders and can be most effective.
If the combust planet (when nearer to Sun) were to be in planetary interchange with some other planet though the planetary interchange has no significance the combust planet yields surprising results.
If the combust planet has in combination with friendly planets, the bad effects of planetary combustion will be pronounced.
Exaltation of a planet gets cancelled if retrograde. If such an exalted retro planet has to its 12th sign an enemy planet, it is as though in a position of fearsome exaltation. If there is an enemy planet in 2nd and 7th, the exaltation of that particular planet is incomplete.
If a particular planet has in its 12th sign enemy planet, it is to be presumed that both planets will yield minimum effects. But if the enemy planet in 12th sign is retrograde, the planet located next to it will yield good results.
If out of the two planets together, the planet, which has more longitude, is an enemy planet and is retro the planet which is less in longitude will yield most minimum effect.
If out he two planets in a planetary interchange, one of the planets is debilitated, the debilitation gets cancelled sue to the planetary exchange. Also if the debilitated planet has a friendly or benefic planet with it or in the 7th or 5th therefrom or aspect then the debilitation gets cancelled.