It will not erase it completely. But it will mitigate it significantly. To be "out" of the influence of astrology, a lot of progress is necessary.
For the majority of people this is the case. SS also experiences it, at different levels. It is possible to "stop it" through knowledge and spiritual advancement.
Yes. For greater accuracy, it is necessary to examine the entire birth chart.
Both. Generally speaking, it indicates problems. When Saturn transits a house, "errors" do not "pass," and the effect, caused by "natural laws," will manifest.
For example, when you have Saturn transiting in 12 house or 1 house, in the case of illegal activities, you will be discovered. I have observed many birth charts about times when people have been arrested or discovered, and Saturn is present, it is not the only indicator but it does matter.
There are times when, for example, it is a good time for illegal activity, to "have," the situations in one's favor, but for ethical reasons, this will not be exposed.