I have played my fair share of mmo's and I have belonged to several RP guilds over the years that have stuck with racial or class purity to enhance the RP aspects of games. One thing that has always crept up was the lack of viability in competitive activities. We always played raids or warzones with a bit of a gimp because we didn't have "The Best" of every race and class in our groups. We were always subject to the limitations of our chosen race and class specializations.
Will ESO finally be that game that allows rp minded guilds to shine? If there was a Guild that say only allowed Knightblades they would have heavy, med and maybe even light armor equipped members with specs in Assassination, Shadow and Siphoning as well as all the other various skill lines not attached to race and class. Will they miss Templars healing specs when trying to do advanced PvE? Or will the ability of anyone to have a healing staff with some points invested into that skill tree be enough? Will they loose out on synergies to much?