It is ok for Team of same region to be helping each other make it through
TSM could be playing SKT and giving C9 hint of how SKT is playing C9 could be playing RNG and help TSM..... CLG could be playing this Team....blah blah blah
Yeah, I don't see this is against any of Riot rules or whatever
I would think it's almost expected for the teams to do a even a little talk-swapping. You need to bootcamp scrim in this lead up to Worlds, and scrimming is easier when both teams can communicate and talk out what they want to see. In addition, Regional teams CANNOT EVER be placed in the same Group because of how the Draw works, so you're certified not to play them in the tourny until at least the Quaters.
Caveat to that is, next year, they'll go right back to playing their rivals in the regular season. I don't think say, EDG just to pull a name/region, would feel confident enough to give pointers to RNG on how to get out of Groups because they very well might leak info about themselves that would compromise their perceived edge at Worlds and the upcoming season.
It becomes a risk; how badly do you want your region and rivals to win, or how badly do you want to keep your competitive edge?
I don't remember fully but there was a team in the LCK that had their Sister team scrim but not show any champion picks, bans etc just play like a "custom" game and don't really try but the objective was to get information from the team that they would potentially be facing down the road without letting the other team get any information from the team that allowed their sister team act on their behalf.
TSM could take their time giving C9 advice on how to beat SKT etc but like I said that is time they could be taking to find ways that THEY can be getting better for themselves also every team plays different so even if TSM tells C9 " oh their weak here and you should go here" for C9 their strengths could be TSM's weaknesses and vice versa.
I think teams from the same region do help each other out some but for the most part neither team really cares much about the other especially if both parties are in the same tournament etc.
