Corrected entry: Why does Chris have his powers when he went to the past if the Charmed Ones never had their powers when they went to the past, for example in "That 70's Episode" or "Witchstock?" If Chris came from the future and traveled to the past, shouldn't he have lost his powers too?
Correction: Maybe in the future they have come up with a spell that allows them to go back in time without losing their powers? It isn't impossible to believe they have improved upon their spells.
Corrected entry: When Orin shoots Piper with the power of the Evil Eye, Leo has to heal her, but she has been self-healing since the beginning of the series.
Correction: The only time Piper was able to self heal was when she was pregnant with Wyatt her first son.
Corrected entry: Why doesn't Chris ever use his powers against demons? We know he can use them in this time, since he blows up Leo in "Oh My Goddess" and kills a Valkyrie in "Valhalley of the Dolls", and after "Chris-Crossed", when it was discovered he was half-witch he had no reason to hide them from the sisters, yet he never once used them against a demon, even when one of the Charmed ones is in mortal danger.
Correction: Actually Chris couldn't use his powers up until the "Chris-Crossed" episode because before this episode the sisters couldn't find out that he was part witch because then his cover as just their whitelighter would have been blown. Basically he had to keep his powers a secret until the "Chris-Crossed" episode.
Corrected entry: In the courtroom when Piper freezes only the innocents, she's not able to freeze the villains when the sisters are fighting with them because she says they're immune to her power. However, in future episodes, she's able to freeze Cole - even though he wasn't an innocent in the courtroom.
Correction: No, you've misread. When they're fighting with the possessed guys in the courtroom, that's when Piper says that they're immune to her freezing power. It's only when they tell her to try and freeze the innocents only. She can't freeze when fighting them though. So why is Cole immune in an episode then not in others?
Before they went in the courtroom Prue came up with the plan for Piper to freeze only the innocents. She wasn't successful at first, and when Cole turned around to face them it was implied he froze but when the sisters chased after the judge he shimmered out and killed him. Notice how nobody else unfroze, so even though she targeted the innocents to freeze, Cole probably figured out what they were doing or saw Darryl and Leo froze and pretended to freeze. He shimmered back in the same spot after he killed the judge to pretend to be frozen again when Phoebe hit him with the baton, so that is why he was not immune to her freezing power because he was not frozen. He was just faking it to keep up his cover, as they did not know he was a demon.
Something Wicca This Way Goes - S7-E22
Corrected entry: The sisters are preparing for a big showdown with Zankou and vaguely discussing their plan. They don't outright say it (so as not to give it away) but discuss how they wished they "had learned it sooner" but "Prue was very protective of it." They're discussing astral projection which originally was stated as a Prue-specific power and not one that could be taught. The show ignored the original introduction of the power as developing naturally as one of Prue's powers, and was not an ability that could be learned, just so the episode had a way for the sisters to defeat Zankou. (00:30:20)
Correction: In which episode did they say astral projection couldn't be learned? In the series, the sisters aren't the only one to learn to astral project and the series has indicated it is one of the few powers that can be taught. Additionally, others have gained this ability through spells or other means. The monkey injected with Prue's blood could astral project.
Correction: Ok, that might be true in some way, but during the whole series, the sisters have proven that they can basically make a spell or potion for anything, that's why they are the almighty Charmed ones. At some point during the series, they had lost their powers (again) and Piper had made a potion to replicate her blasting power. So it is totally possible that Prue had figured out a way to replicate her natural power of astral projection trough a spell. When the triade first came into the picture, Prue studied the Book all the time and practiced her powers in every way that she could so she could protect her sisters. So it is entirely possible that she found a way to share her power.
Correction: Bianca states in Chris-Crossed, that with the particular spell that they were using to send him back, his powers would not be affected.