[baking]

They way I would describe it is that 3-way ties are very stable. Backstabbing to get into a 3-way tie is certainly considered fair game and there should be no hard feelings among experienced players.

But not respecting the 3-way is a whole other thing. 2-way ties are extremely tricky, so eliminating the third player will usually result in a solo win, often with the third player throwing in to punish the perceived aggressor.

So experienced players do tend to play for the 3-way and will only work with others that they know will respect the 3-way draw. On the other hand, solo wins are wicked fun and one solo win is worth ten 3-way ties (even though tournament scoring and other rankings don't reflect that fact.)

EDIT: I should add that there is one other dynamic that comes into play, and that is that 4-way draws are really frowned on by many players. A larger player with a smaller ally that stays "loyal" to their small partner can force the elimination of a medium size power that would otherwise have participated in the draw and that can upset the apple cart, possibly in the larger player's favor. But this strategy is pretty transparent and is usually unsuccessful among better players.