Well when you write fanfiction stuff for as long as I do, you learn that you're gonna always play more than one character at a given time. And it's less about playing them and more about writing a story in general? Like, you're caring more or less about the plot and that as a whole rather than just your individual character, right? Essentially, in a roleplay you're not just caring about your development but as the group as a whole. More characters sound harder to deal with, but it's par for the course for any kind of novel. But it's weird to compare novels and roleplaying. One's more stressful than the other and I can probably assume you know which. roleplaying fuck dealing with all these nerds in here JUST LEMME SHIP MY STUCKY
That's like asking J.K. Rowling how she can write for 20+ characters at a given time hint: she's actually a goddess in disguise.