http://comic.dragonballcn.com/list/0.Dragon_Ball-buyao_daolian_ya/0.jp_Kanzenban/DRAGONBALLvol27/119-WHV6a.jpg
To be precise Cell said "close to some extent" rather than straight up close. I think Viz omitted the "to some extent" part like they sometimes omit parts of statements.
This is in pretty stark contrast to Freeza's Kiai causing Goku pretty intense pain, and Goku displaying no real discernible advantage until Freeza's stamina began to fall visibly. I agree with SSJ2 here. The two gaps aren't comparable.
That aside, yeah I've always felt that people underrate the gap between Goku and Cell because of the post-Kamehameha fight performance that was more even. Cell had to compensate for both the damage taken from the KHH and expended Ki from regenerating, so that part of the fight doesn't truly...
Water itself isn't the problem but the low variety in mons found in the faggot water surely is. You can only run into the same 3 Pokemon over and over enough times before you want to just spam repels.
Goku probably got stronger from the consecutive battles he had with Nam and Roshi, and then received a zenkai from the super gun attack he took to the back of the head in the Muscle Tower. I don't think Blue posed enough of a challenge to Goku outside of telekinesis to cause much of a gain. I...