Really doubting this, given Plagueis' performance against the Maladian assassins while suffering from a partial amputation of his jaw and neck, several gushing blood vessels, and two of his three hearts failing, while the third compensated for all cardiovascular functions independently... and his proximity to Sidious.
Didn't really aid him against Katarn and co. Caedus learned some cool abilities, but his precog being better than Plagueis/Sidious' is dubious.
It was a stalemate in the end, but your point is taken.
Plagueis was at least equal to a Sidious who moved so fast, and was so skilled, TPM Maul wouldn't be able to a lay finger on him, let alone react in a meaningful way. We can go back and forth about who's better out of Maul and Jaina, but I think they compare favourably enough to each other. And I sort of doubt Caedus is so much better than Jaina he would essentially blitz her. That's not really supported by any of his showings, namely fighting the Katarn group, which as a feat, is comparable to what Grievous did on Hypori, let alone what the higher tiers of that time period, like Plagueis, are capable of.
Not to mention, you're suggesting we create a bifurcation between Plagueis power as a Force wielder and his power as a fencer - but the two are intertwined, much like they are with Caedus. And since we're aware Plagueis is conclusively more powerful than Caedus, it makes sense that for the same reasons, he'll be a better duelist, and I think the evidence supports this.
__________________ “The galaxy must experience the pain of death and the rapture of rebirth as I have. I will bring chaos. It is time for war.”
Plagueis is both more feat-wealthy in objectivity and has better implied power thank you very much. There is enough for Plagueis in a single book to mog the feats battle hard, despite his opponent having been in 100 times more sources. There was, for example, no point in said book where Plagueis was ever pinned and overpowered by a single mandalorian warrior, but instead a scene were he was dying from severe bloodloss and heart failure (i.e.- a worse state than Caedus against Jaina) and he still put his hand through armoured torso. All pre-Force unbalancing.
If fight sight lent Caedus a guaranteed victory in lightsaber battles, it would have saw him though circumstances where he opted out of a duel and started throwing things at his opponent. If it's just enhanced pre cog, than the power gap can make up for it here. We've seen Plagueis reach a similar state against Venamis... However, assuming this technique is beholden to the same limitations all force powers are, using it probably means he's making a compromise - enhanced perception at the cost of augmentation, perhaps? Which would explain why he never used the technique to automatic victory against Luke, Kyle or Aurra Sing.
He's definitely the more powerful force user, and probably more skilled too tbh regarding Sidious' training. The onus is on you to provide evidence that "fight-sight" is a game changer in all this.
Jaina at this time not even being ATOC obi wan level, as implied by her own statements and a lack of contradiction from all those within earshot.
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“We defeated the wrong enemy” - General George S. Patton, Berlin 1945