All right, I promised the OP I would post a counter-analysis to this so here it is:
Firstly, I accept that when amped by a DS nexus Nyriss' lightning is superior to Dooku's - and I accept that Yoda struggled against Dooku's lighting whereas Revan seemingly did not. However I reject this as proof that Revan is anywhere near Yoda's league in terms of power.
And this is because the OPs theory is flawed, because he assumes that Yoda's struggle against Dooku was down to a lack of Force power as opposed to age induced infirmity and over-dependency on a non-combative/scholarly environment to use his Force powers - which in fact, is evidently the case.
Yoda is a scholar, an aged scholar who suffers from arthritis among other things, and because of that Yoda finds it difficult to build up and exert his vast reservoirs of Force energy on his environment. And this is why Yoda struggled against Dooku, not because he lacked power, but lacked the ability to quickly exert it. He was old, frail and slow - but still vastly powerful.
And this is a view that the Jensaarai, who you may be familiar, concurs with. Here is his summary of the topic - relevant until the 32:00 mark.
Indeed compare the following:
Here is Yoda warding of Dooku's TK attacks, note the slow deliberate motions and the obvious exertions it takes for him to do this. Something decidedly absent from the lesser Dooku's attacks. Yet here we have two far younger and more combat-experienced Force Users throwing around projectiles with consummate ease. And then again here a similar pair also wield TK without the exertion Yoda displays. Neither Ventress, Anakin, Malgus or Darach are in the same league as Yoda, and yet - because they are younger and unlike Yoda used to using their powers in the field - they are able to use TK far quicker than he.
And yet we would not argue these individuals superior or even equal Force Users. For despite Yoda's age and scholarly persona, when he is able to bring his full powers to bear through concentration they are vast to say the least, vastly superior to what Revan is capable of.
To apply that to the example given, Yoda would have struggled at first to absorb and redirect Dooku's lightning because it would have required an immediate and unexpected response, which Yoda is not geared towards, however once given time to concentrate, he could negate Dooku's attack with little effort. The novel and the film, demonstrate this, in the film the visible signs of exertion are in keeping with his previous difficult in deflecting Dooku's TK and the overall concept as Yoda as old and scholarly. The novel itself elaborates on this, noting that as Yoda is given time to concentrate, he becomes increasingly more confident and ready:
...but Yoda continued to catch it and turn it, and seemed to become even more settled in his defensive posture.
"Much to learn you still have," Yoda remarked.
Dooku disengaged the futile lightning assault.
--Taken from Attack of the Clones novelisation
And here is the Offical Databank's take on the event:
The Sith claimed to be more powerful than any Jedi, but Yoda easily absorbed his Force lightning attack.
Which, may I add, is canonically superior to the novel anyway.
Revan on the other hand, a practiced, younger warrior who like Anakin, Ventress, Malgus and Darach had been in many battles and became accustomed to use his powers quickly, had no such difficulty in gather his energies immediately and deflecting Nyriss' power.
So again, the premise that Yoda struggled due to a lack of Force ability is flawed, he did not, he struggled because he was out of his element. A far more accurate comparison, to properly compare Revan and Yoda's abilities is to show them at their absolute limits rather than trying to draw flawed conclusions from circumstantial evidence. Instead substitute Nyriss for the Sith Emperor and substitute Dooku for Sidious. For in those engagements where both Yoda and Revan pushed to the limits of their abilities and by comparing their limitations we can accurately compare their power:
Here is what happened when Revan tried to catch the Sith Emperor's lightning:
A dozen bolts of purple lightning arced from the Emperor toward him, Revan tried to draw them in and contain them but the Emperor was infinitely more powerful than than Nyriss had ever been. Revan's body was engulfed in agony as the electricity coursed through his body, his skin began to boil and blister, the flesh of his face melting and sticking to the superheated metal of his mask as the Emperor poured more and more power into him.
--Taken from The Old Republic: Revan
To say he struggled would be an understatement, as it is quite obvious that had T3 not intervened Revan would have shortly died.
Noting that after:
...the Jedi collapsed to the ground, burned, but still alive
and he was:
...almost too weak to move
Revan was, quite simply, totally surpassed by the Sith Emperor's power.
Now, to compare that to Yoda's performance against Sidious who is comparable (though markedly superior) in ability:
http://www.youtube.com/watch?v=S5SkNrWSk5M&t=5m21s
The difference is staggering, Yoda is not only capable of catching the full brunt of Sidious' lighting without being burned, but he was able to gather his energies and push them back, almost completely overwhelming Sidious before the energy explodes and luck has it that Yoda loses the high ground.
I don't think I need to go into much more detail here, Yoda was able to capably catch Sidious' lighting and almost overwhelm him, whereas against an opponent of similar (though weaker) strength Revan was not only incapable of fully catching the bolts, but was almost killed by them.
Yoda is clearly the superior wielder of tutaminis here, grossly superior, and this only reinforces the fact that Yoda only struggled against Dooku because he was out of his element. To conclude I would draw your attention to Yoda's initial inability to contain Sidious' energy, thanks to his age and scholarly persona, yet after having time to concentrate he pushes back and gains the advantage, and it is at that point that the full extent of his power comes to bear.
TL;DR Yoda struggled against Dooku because as an aged-scholar he was not used to exerting his powers quickly, yet clearly Yoda is grossly superior to Revan given his performance against the Sidious in comparison to Revan's less than impressive performance against the Sith Emperor.