Steelwing vs. Dragon Tail: A contrarian view

You usually can get two DT in between quick moves, though. You'll only find trouble against the faster moves like Water Gun, Pound or Lick, but they're so weak that you'll be better off not dodging them anyway.

I like steel wing more (0,8sec).
Its easier for me to spam it and succesfully dodge charge moves when needed.
I use it vs snorlax and Blissey.
(edited, changed chansey to blissey obviously)

I think im gona power up my Venusaur for vaporeons.

Your analysis isn't bad, its just that I prefer my Dragonites with Dragon Tail because its resisted by less pokemon types and most rival gyms in my area have lots of Vaporeon, Gyarados and Dragonite.

Dnite is also fairly tanky so there is little reason to dodge weak defensive moves...FunkySho did a video that shoed dodging quick moves actually loses more health due to wasting more time, thereby, taking more damage overall in most cases...

DT just does so much more damage that you're better off spamming over weak attacks and you should be able to dodge with 2 for the slower, more powerful defensive moves...

As others pointed out you can fit two DT in every dodge pattern

The biggest bummer for SW is the NVE vs fire and water and non super effective damage against Dragonite.

SW is undoubtedly superior against Fairy however, but there is no charge move to couple steel wing with.