You guys do realize that Sideous had probably forgotten more tricks than Caedus knew about
Not necessarily, Cadeus went on that trip in search of unique force powers, Sidious (per the Rule of Two) learned the accumulated knowledge of the Sith then killed his master and focused on his political schemes. As opposed to Caedus, who learned from many diverse force groups as well as Sith and Jedi).
it is arguable that Caedus was stronger than Yoda in raw potential, but he was fairly in-experienced. Yoda probably could beat Caedus due to the lack of experience.
Caedus was impressively calm, patient, and disciplined in almost all his fights (save for those with his family). I think his experience in battle is easily a match for Yoda's, even at Yoda's age. Jacen acted far older than he was all the time from the Vong invasion to his death.
Remember Luke nearly killed Caedus on Caedus's own flagship, if Ben Skywalker hadn't been the psychological mess that he was (courtesy of his cousin), quite frankly the Legacy of the Force series would have ended back in the book Inferno.
In the Inferno fight it was Ben's stabbing Caedus with a knife, that won Luke that fight and he didn't finish Caedus off for fear of falling to the Dark Side (thus it took Dark Side tactics to beat Caedus that time). I admit Luke could have killed Caedus but honestly, EU Luke would kick our little green friend to the curb so it's not fair to compare the two based on that.
Also Luke commented that he saw something horrible would happen if he took on Caedus (see Invincible), where Luke actually said flat out that it would be cause Luke would win, not Caedus.
I covered this one above well enough I believe.
In short, Caedus wins this. His Skywalker force potential, combined with his heightened and honed battle senses, his lack of pain, and his impressive array of unique force skills rivaled only by Luke himself, Caedus is just a bit too unorthodox and just powerful enough to defeat Yoda.
On another note and one that is often overlooked, is Jacen/Caedus was an EXCEPTIONAL duelist with a saber, even being put on the level of Luke. Heck he fought Jaina with one arm and hole in his stomach and she still needed him to be distracted in order to kill him.