Isn't Cell proof that Gero knows how to mess with DNA(though admittedly yeah the computer did most of it in that case)?
Yeah, I kinda figured that that was the case when I thought about this. Passing down genetic changes is very possible and very expected if 18 gave such a hint.
And speaking about genetics I find it interesting that no one points out the in the dbz world Saiyans must be genetically very close to humans as Gohan and Pan prove. But this just my Geekdom 101 showing, I'm sure not one really thinks about this much.
How do you explain it taking the main star of the series who we safely assume is the strongest outside of maybe Jiren and his chief rival taking years to achieve a legendary form but these super rookies from an alternate universe getting a tingling feeling in their back and getting massive power upgrades? It's bad writing just meant to make them able to compete in the tournament of power if you ask me. It's obvious Goku and Vegeta are better fighters.
This is gonna be a long one ... sry :/
Why would you ever think them rookies?
1- Different universe means a hell of a lot. Sure, U7 has had other worldly threats like Buu and Freeza but U6 Saiyans are professional space mercenaries who fight for peace. Going out and fighting things like that is normal for them.
2- Environment. U7 earth is not the best training grounds for the few Saiyans left alive in that universe. Only a legit hand full of people there are strong enough to even fly and much of that hand full have no desire to train now that the Saiyans have dwarfed them in strength. The only known beings in their world that could threaten to destroy earth is the GoD and Whis.
But lets for a moment imagine a world of Saiyans that were well known space mercenaries and lived peacefully for the most part, not wasting potential powerful members of their race based on baby power levels and power based caste systems. A world where I'm sure much of the population can fly and throw fire balls and desire to get stronger. Seems like a much more healthy training environment that pushes it's people to become stronger as a whole. This type of setting lead to base Cab, one of their strongest Saiyans, being as strong as base Geets (as we all know forms are a multiplier. So the better the base the better the form). I see no reason why these Saiyans shouldn't be this strong given how they live.
3- I think their environment actually explains why they never unlocked SS. Think of how Goku got it. He was in a situation where he was the only one even remotely strong enough to face Freeza at the time and everyone else just served as emotional triggers and added stress that lead to this transformation. U6 Saiyans wouldn't have these problem because of their different culture and setting. Like, what if Goku went to fight Freeza with a team or small army of Saiyans around his power level (some even stronger) at that time who had no problem fighting together? Even if none of them were as strong as Freeza the collective power and number advantage would mean that they wouldn't have that stress that made Goku go SS.
The way I see it to trigger SS transformation you have to at least have a base that's like .... lets say This "------------------------------------" Strong.
Goten and Trunks were already that strong as kids for w/e reason (epigenetics maybe) and I suspect that MANY U6 Saiyans are as strong or stronger than that.
To get the higher forms like SS2/ Ultra/ SS3/ SSG/ SSB you have to have a base that's much stronger than that. What we have here are 3 U6 Saiyans with bases as strong as Geets and Goku (I'll just put Goku there because. I'm mostly going off of Geet's comments in his fight and applying that to the other 2). Once they learn to get SS unlocking greater forms seem like it should come natural IMO. If they're already strong enuff to match Base Vegeta after all this then why would pushing past something he's surpassed already be that hard?
4- I think tingly back is how they all unlock it. Geets never explained it to Cab that way cause he's fucking Vegeta and accidentally finding it on your own through anger and stress makes sense to him. Goku is the same way I think.
So yeah, they're a race of space mercenaries and these are 3 of the strongest, why wouldn't they be strong?