When I do manage to create a board game, one phase of that process is solo-playtesting. I essentially take on the role of all of the players in a bid to find something wrong with the game. I figure that solo-playtesting is a good way to see if a board game design is viable or not.
However, solo-playtesting also has it's drawbacks (as I have discovered over the years).
First, because you are playing all of the players, you 'know' your opponent's moves and can counteract them. This can lead to drawn out games and skew just how quickly a game resolves itself.
Solo-playtesting might also not detect first- or second-player bias unless you are really careful. I had one design that I thought was really good. However, upon further testing, I realized that an aggressive player of that game would (almost) always win; I hadn't taken into account certain variables that were obscured by assuming all of the player's roles.
When do other designers take their designs from solo-playtesting to playing with actual other people? Part of my problem is that I solo-playtest until the point of exhaustion (mainly because I want to catch any major flaws before even tell other people that I've made a game at all) and then let the game cool off, psychologically giving myself the excuse that "I've done enough" and it's time to move on to other projects.
