@Tangaroa:
Also got told it was ridiculous when asked if Sanji meaning third son could mean he had brothers.
Congratulations. That's completely irrelevant to what we're talking about.
My reasons for suspecting one was Mr.6 being the only under 10 member we never saw
For starters, so what. But mostly you're creating a totally arbitrary importance border that doesn't exist. Meaning that being under ten isn't important or meaningful at all in Baroque Works. The ranking border in BW is between 5 and 6, not 9 and 10. 1-5 are the officer agents, and 6-12 are the frontier agents. Meaning you don't remember or don't understand at all how BW works. Mr. 6 is a frontier agent so not seeing him is about as relevant as…well its really not relevant at all. The frontier agents were pretty unimportant toadies who existed to conduct bounty hunting operations to make money for Crocodile's plans. You're talking like they were important players, but nope. Not at all.
My reasons for suspecting one was Mr.6 being the only under 10 member we never saw
So as a result that makes you obviously wrong then. Because we never saw Mr. 10 or Mr. 12 either. But even your basic statement is wrong without correcting for the actual rank borders. Because you're entirely fixating on the male members for some reason. We never saw Mr. 6's partner (Ms. Mothers Day) either, but you don't seem to care about that.
that it was at Alabasta Sanji made his own play around Crocodile.
Huh? What is this referring to? Sanji saving the day at Rainbase? That wasn't the first time he did his "Sanji vanishes and reappears having done something useful out of nowhere" thing. Not exactly anyway, his first time along those lines was Little Garden when he vanished for nearly the entire arc, and ended up discovering Mr. 3's camp and making Crocodile think the Strawhats were dead and also got an Eternal Pose for Alabasta (and took out the Unluckies). That scene also set up the Rainbase incident too. Now of course….what the hell does this have to do with Mr. 6, let alone Mr. 6 being a brother. Literally the only connection is Sanji doing this thing in an arc where Baroque Works was the main villain..?? So...??
His other solo play, slipping away to open the tidal gate at Ennies Lobby,
That's not his only other solo play. Aside from a few more minor times that could count, like saving Tashigi in Punk Hazard. The other major time was in Water7, he vanished for almost two volumes, missing the whole CP9 attack on Galley-La…then popping up at the train station just as CP9 was leaving with Robin.
came from his direct knowledge as a Vinsmoke.
….what? You've completely made this up. If this a hunch of yours why the heck are you stating it like established fact?? And if its a hunch you can't use that to argue another hunch, that doesn't make any sense. A hunch isn't evidence lol. Besides I don't even understand this hunch in the first place... why would being a Vinsmoke mean anything regarding this? And we're SHOWN where he came up with the idea, Sanji and Zoro have a scene where they meet after beating Kaku and Jabura and are looking out a hole in the wall toward the gate. They're both mentioning how they notice that the whirlpools vanished when the gates opened. Setting up Sanji to go look for a way to close it later on.Didn't phrase correctly, instead of another I should have said 'one of'. As for power level I would be guessing that it was an undercover job, like CP9 on Water 7, to scope out BW. Though the family is famous by name nobody has mentioned Sanji having a family resemblence before so I don't know how recognizable the individual brothers are.The main reasons I can think against it are that the Vinsmokes are more army and less special op, though the assassination motif their fighting styles have originally threw me, and that Robin never commented on knowing someone who looked like Sanji. But Robin does tend to keep information rather close sometimes.
As for power level I would be guessing that it was an undercover job, like CP9 on Water 7, to scope out BW.
Why would the Germa be scoping out BW? We have absolutely no reason to think this. They're shown working on two different sorts of things so far. Mercenary jobs, and trying to get back their North Blue empire. Why would they care about BW?? Who would hire them?? Alabasta obviously didn't since their literal heir apparent did an undercover job herself, and the government was shown to be clueless about it by Smoker being the first one to sniff out a conspiracy on their end. CP9 had an incredibly good reason to be doing undercover work on Water7, and are also literal spies. The Germa aren't spies, in fact they're ridiculously flashy and aggressive. Your theories evidence requires evidence itself lol.
The main reasons I can think against it are that the Vinsmokes are more army and less special op, though the assassination motif their fighting styles have originally threw me, and that Robin never commented on knowing someone who looked like Sanji. But Robin does tend to keep information rather close sometimes.
And among all this you never mentioned a REASON for this to exist as a thing in the first place. We never saw Mr. 6, who played no role of important in anything. So why would him being one of Sanji's brothers even matter or exist for Oda to write in the first place?