Sun, Saturn and the 12th lord from a Rasi serve to separate the individual from the concrete experiences of the Rasi...I have having a hard time putting this together. For example, someone has Sun, Saturn, Venus and Ketu in Scorpio in the 8th house...does that mean all the action there is largely mental and emotional? Does that mean we do not take those planets into account for concrete reality? Or when those concrete experiences happen...they are separated from them and develop a psychosis? I don't clearly understand how the separation is meant to be here.
Sorry for needed it broken down pb&j style!
In your example, one of the way it could play out for Aries Lagna: Sun rules the 5th house of children, creativity, spiritual practices; Saturn is the Lord of 10th and 11th - actions out in the world and career, and the gains from it; Venus rules 2nd and 7th - being in resourceful partnerships. Ketu creates a security paradigm with depending on partner's or other people's assets and resources (besides the mental and emotional indications of the 8th). They are naturals in sticking to the hardships and the ugly side of codependent situations and even unhealthy ones, and they smooth things over for the sake of others.
Then when the right dasa and transits come along, Sun may separate the nativ from the 8th house stuff in order to get them to focus on their inspirations, knowledge, projects (creativity) or kids; Saturn may separate them from the 8th house because in order to focus on the 10th and 11th house - but Saturn separation is way more painful and "unwanted".
How successful they'll each be at taking care of the houses they rule, depends on MARS is doing and its condition and aspects, because he rules the Lagna and this 8th house. He's naturally supporting the Sun in scorpio, but he is a natural enemy of Saturn. If Mars happens to be in good dignity, in the 2nd, 3rd, 4th, 10th, 11th, 12th from Scorpio, and with good and helpful aspects - then he will support SUN better in his actions and cause less enemy trouble for the Saturn.
Because Sun is in a friend's sign, but with enemies Venus and Saturn, and with Ketu - it may feel like no matter how much he's trying to do what's right, it isn't well respected and it's not enough, and that can hamper his inspirations.
Because Saturn is in an enemy sign, with enemy Sun and friend Venus, plus Ketu - it may feel frustrated and burnt out and like a whirlpool of unfairness that he/she can't get out of, all because of others, but it's not all bad as long he/she can get a fair amount of satisfaction(Venus). It might have a harder time take care of its duties in regards to 10th and 11th.
If Scorpio happens to have an EX Jupiter smiling on it from Cancer, let's say, that would lighten up the burden, the emotional one - but also the one regarding joint assets, codependence, dealing with instability, losses, secrets, fears, etc. There is a general sense of hiding and shame that still remains due to combination in Scorpio though. That can get worked out by working on brining health to Taurus, 2nd house and 2nd Ld=Venus, thru trial and error.
I usually suck at explaining - so if this got confusing or if it didn't answer your question, let me know...
Also, the 8th house rules real things we can be separated from, such as other's people's money, and its also the strength of the marriage bond so it can cause people to separate as well.
Saturn is still starving that planet so that planet will struggle to give fulfillment. IN the dasa of saturn that planet can get manifested since Saturn rules it.