When did Palpatine's lightning lit up a planet's surface? You are talking about Sidious contacting Dooku on Vjun via hologram? If so, then Sidious didn't light up the planet's surface, it was just a poetical depiction of Palpatine's character. Not to mention that his Force lightning(blasted Kadir and some stormtroopers: but it didn't ash or charred husk'd them)
He only achieved that feat on Kalakar Six(a dark side nexus) and on Byss when he disintegrated those stormtroopers)
He even blasted Windu with all of his power, and it couldn't ash or charred husk him.
__________________ The Ellimist: "Nadd is the 90 IQ guy who acts like a 70 IQ guy to make fun of the nerds"
I believe they grew stronger, but not as ridiculously as some people think.
It took them nearly a millennium to finally pass Yoda in power, Yoda who had no RoT, power scaling/building behind him. And if you want to make age=more time for knowledge=higher power, as to why Yoda is so powerful in proportion to the vast majority of the Banite Sith, you would then have to apply Vitiate/Revan etc, to the same logic.
Your logic is off though: there is clear evidence that Yoda doesn't get surpassed until the end of the Banite line, while the whole point of Banite scaling in the context that you're responding to is to scale the Banite Sith against other characters, so you can't circularly declare that Revan and Vitiate must also be near Yoda. Banite Scaling helps Yoda too.
Sorry? there evidence suggesting otherwise as well.
Yoda/Mace they all come close to Sidious, without Benefiting from some RoT type power up. It suggests, the RoT power up, is not as large, as one would claim.
You guys exaggerate it to be dozens of times more powerful. Which is illogical, when Anakin technically was only twice the potential of Sidious, which is tiny to what the growth of the RoT is, it would suggest Sidious's potential successors, apprentice, would be Anakin level in growth. Which is retarded, within context of the SW universe.