I copied and pasted this argument that I remember. It's just one excerpt.
Edit: Credit to Publius, 100%. There's no way in hell I could even dream of something like this.
"The most powerful of these" refers to the Sith Lords of the Sith Order, descending from Darth Bane. To suggest that it refers only to Darth Sidious and Darth Maul requires a certain level of willful ignorance of the English language. If Sidious and Maul are the only Sith Lords being described, then they would have also spent the previous thousand years watching and waiting. This is a highly dubious contention.The Dark Side Sourcebook does not attribute the ability to conjure Force storms to the Imperial Sith. The ability "Summon Storms" refers strictly to meteorological phenomena, and is attributed to generic dark side witches and to the Nightsisters Gethzerion and Tamith Kai. Vague citations such as "the sourcebooks" are hardly fit for serious discourse. If no specific citation is offered in support of a claim, that claim does not merit consideration.
Although Imperial Sith are noted for their longevity, their parochialism makes them significantly less impressive. A Jen'ari of the Sith Empire may well have ruled for hundreds of years on end, but he ruled only a few hundred primitive worlds in the galactic periphery, far from any potential rivals (The Dark Side Sourcebook even points out that Marka Ragnos "believed the Sith were not yet ready to enter into a protracted war with the forces of the Republic"; The Fall of the Sith Empire shows clearly that these 'enormously powerful' Sith Lords were defeated by the Republic). In contrast, Darth Sidious seized control of the vast majority of the galaxy, and built up an extraordinarily powerful galactic superpower that ruled billions of worlds (The Star Wars Roleplaying Game, Second Edition - Revised and Expanded). He orchestrated the complete destruction of the Jedi Order, which out-numbered his Sith Order by a factor of roughly 5,000 to 1. Judging by political standards, Palpatine was vastly more powerful than any of his potential rivals.
In terms of preternatural abilities, the only way to compare them is to judge them by their deeds. Simus was able to survive as a disembodied head for 100 years (The Golden Age of the Sith); Palpatine was able to survive complete corporeal destruction and travel thousands of light years from Endor to Kaal (Return of the Jedi, "The Emperor's Pawns," Dark Empire Sourcebook). The ancient Sith Lords developed a means of allowing their ghosts to possess the bodies of the living via having their hosts lay in custom-made sarcophagi ("The Sith Compendium"😉; Palpatine possessed the body of Jeng Droga completely unaided ("The Kaal Connection," "The Emperor's Pawns"😉, repeatedly reincarnated in the bodies of clones, also unaided (Dark Empire, Dark Empire II), and was very likely able to possess the body of Anakin Solo unaided (Empire's End).
As noted earlier, Palpatine was struck squarely on the head by a ton of machinery, and shrugged it off (Dark Empire, Star Wars Handbook Vol. 3: Dark Empire). He was capable of moving so quickly that the eye could not track him (Episode I Journal: Darth Maul). He created a hyperspace wormhole and projected a Force storm from Byss to Coruscant, and displayed sufficient fine control to physically translate Skywalker from the planet's surface to the hold of a Lictor dungeon ship (Dark Empire). In a matter of seconds he summoned a Force storm and destroyed at least five capital ships, and accidentally destroyed two Star Destroyers and a Super Star Destroyer when he lost his concentration (Dark Empire). He was able to feel immediate danger to Darth Vader on Mustafar in the Outer Rim while still on Coruscant (Revenge of the Sith), and could communicate telepathically over vast interstellar distances ("Sleight of Hand: The Tale of Mara Jade"😉.
There is a distinct difference between the Sith Lords of the Sith Empire (e.g., Marka Ragnos, Naga Sadow, and Ludo Kressh) and the Sith Lords of the Sith Order (e.g., Darth Sidious, Darth Maul, and Darth Tyranus)."Taken by Force" (Star Wars Galaxy Magazine #8 specifically notes the following:
Quote:
Get one thing straight: The dark side of the Force and Sith magic are not interchangeable, and the comics have made a firm distinction between the two. "The Sith and their abilities were hinted at in Tales of the Jedi and Kevin J. Anderson's Jedi Academy trilogy," Cooper says. "There was a connection with Exar Kun, who was Force-adept and had a strong will to seek out Sith knowledge. Kun added his knowledge of Sith magic to his arsenal of weapons."
The most impressive feats of the Imperial Sith -- such as Naga Sadow's cruiser causing major stellar catastrophes -- were wholly dependent on the use of artifacts and talismans (hence the ease with which Exar Kun was able to master Sithian magic, to say nothing of completely unskilled practitioners like Satal Keto, Aleema, and the Krath). They were invariably seen wearing such magical accouterments. Any given display of preternatural abilities is tainted by the fact that the Sith Lords were actively using Sithian magic, which required no effort at all to use (The Freedon Nadd Uprising).
It is worth pointing out that although Sidious is not known to have used any such arcana when performing his own feats of Force mastery, he was exceptionally well-versed on dark side lore and was a known master of Sith magic (the Dark Empire Sourcebook notes that he had long ago mastered the knowledge of the Krath, who were strictly Sith magicians). He was an accomplished alchemist and is known to have been in possession of a number of ancient Sithian artifacts, as well as having traveled to several of the 'holy sites' of the Imperial Sith (Drommund Kaas, Vorzyd V, Yavin IV, Ziost, and Korriban). He was familiar with their methods -- and generally did not use them.
It is not enough to merely assert superiority and then expect to be disproven. One has an obligation to provide evidence to support one's claims. There is no reason to believe that an of the Imperial Sith were more powerful than Darth Sidious. If one is to claim otherwise, one is of course required to provide clear evidence. If specifically comparing physical abilities, then one must be able to cite discrete incidents.