With Dynamic Groups, Season 6 ranks will be a hilariously inaccurate indicator of skill
Me and my Silver friends will get Plat next season easily, if not higher. I know this because we go against Plats and win in Ranked 5's. Mechanically we're all pretty average, but we've been playing together so long our teamwork and communication typically trumps individual shortcomings.
But we'll still be Silver players, our Elo will just be ridiculously inflated because soloq will allow us to play together and abuse the fact that we've been playing together for years.