What a difference 30 years makes. Obviously. In this case though, I’m referring to Star Wars and its approach to the Light and Dark Side of the Force.
In the original movies there was the Force, and there was the Dark Side. The Light Side was never mentioned, but was implied to be the base default, of which the Dark Side was a corruption. Yoda’s words of ‘Once you start down the dark path, forever will it dominate your destiny’ seemed absolute. Indeed, it was implied that only Vader could be redeemed because of his sacrifice to save his son, and that this was a rare and exceptional event.

The EU on the other hand has had a lot more to say about the Light and Dark. On the one hand Jedi and Sith regardless of who they care can and do fall and be redeemed. By the time one reaches TOR there are Dark Council Sith Lords being redeemed, Jedi falling and being saved, and an all-around atmosphere of a revolving door.

And SWRP? Well, the revolving door here, like other sites, is in full swing. Some characters have fallen, been redeemed and fallen again. Back at the Craftshop there was almost literally a constant in and out of Jedi and Sith.

Is this a problem? Not especially. People want to be able to play their characters as they wish, and changing factions is usually more of an OOC than an IC thing.

On the other hand, it’s never really made sense to me how one being redeemed can just be forgiven. Unless one’s mind was actively controlled by someone (like Revan by the Emperor) does the Dark Side really nullify one’s actions? Take the obvious other example of a Republic Admiral who turns traitor and joins the Sith, only to regret their actions and returns later. Would they be treated in the same way? Doubtful.
Therefore, the theory only works if we assume the Dark Side is a parasitic life form in itself which is actively controlling people…yet the evidence from the EU and movies does not support this. Is then the Dark Side just down to the person using it, and not an outside influence at all? That would seem more logical, but again is not explained.

In the end, the mechanics of how the Force works has been built on so much over the years that until the new movies and novels spell it out we are left to speculate.