When did one fighter turn Super Saiyan and get a 25x boost, while the other turns Super Saiyan and gets a 10x boost?
Absorbing Piccolo again allows Gero to beat Vegeta, and absorbing the humans allows the same.
They are implied to both grant the same advantage.
No one at the same time. At a same time frame and under same training, I've all Saiyans getting exactly the same boost, with the only, exceptional and minimal exception being EoZ Goku due to what I said, my theory that he's approaching his limits and his training, as he evolves to his ultimate-like state, is bringing all that power into his base state, making the base ~ SSj bridge was smaller, accounting for the Ultimate Saiyan warrior accessing all that power into a normal-like state. Gotenks unlocked more of the fighters potential and as long as they break thresholds, the gap between forms shrinks, which is wheh it went from 25x to 10x. 25x was already a diminished gap post them mastering the SSJ, already being a step towards the final warrior evolution and managing to access more power in their base states than they normally would, before mastering it.
They are implied to get Gero where he thought he'd get the job done... That doesn't mean they'd increase him by the same amount, as Gero didn't specify the ease in which he'd have dealing with Vegeta in each case.
Btw, do you agree Gero's estimations in dealing with Vegeta was off, right? Hw could tell how much power he'd get, but couldn't rightly estimate Vegeta's powers, true? If I were to consider Piccolo's supp power like his base power and assuming the 1:50 SSJ ratio, he could be 7,400,000 then.
If I wish to make Piccolo = Gohan + Tenshinhan + Kuririn, then...
It'd be far assuming Gohan would make 60% of Piccolo's power and the earthlings, the other 40%, with Kuririn filling the majority of the 40%
Piccolo 7,400,000
Gohan 4,500,000
Kuririn 1,750,000
Tenshinhan 1,300,000
There you'd go. Gohan would be weaker than where I'd generally have him. It's not a big deal though considering he preogressed quite a bit on his own before sparring with Goku, and judging by their sparring, he was still not on Goku's level initially.