The problem with using Dugtrio on a rain team is finding room for it. You usually have three rain sweepers, a rain lead, and two mid-game supporters. Dugtrio can't learn Rain Dance, so it can't replace a supporter. You could only have one mid-game supporter, but only having one is a very bad idea. You could run Rain Dance on one of your sweepers, but that severely limits their options, since most rain sweepers need all four of their moves. I can see how it would help in getting rid of Raikou, Toxicroak, and possibly Venusaur (I say possibly because I haven't run damage calcs), but there is just no room for it. It is better suited to a sun team, since it can learn Sunny Day, sun doesn't power up a type it is weak to, and it can get rid of opposing Fire-types.
Since you say you have used Dugtrio on a rain team, I'm interested as to what you replaced. I'm not being sarcastic, I'm just curious.
Since you say you have used Dugtrio on a rain team, I'm interested as to what you replaced. I'm not being sarcastic, I'm just curious.













