edit: Here's the link to wgeurts team writeup.
You're taunting their setup, and probably being fast enough to set up TW next turn. It's still weak to Crobat/Tornadus/Blimp because those three can match your setup, so it's ends up being kinda dead weight, at least from my experience. But on a HO team I was bringing it every single game unless my opponent had one of those three. The flowchart for me was lead incineroar + TFlame, fake out and taunt, tailwind and uturn into either CB Don or Specs Ogre depending on the team, or Xerneas if it made more sense given their board state. Then Brave Bird to die and bring in the other one, or if they bring in Fake Out to try to stop it you can quick guard. However, that was just my team, I don't know if other teams play the same way.
Tapu Lele usually isn't an issue because your opponent will normally either attack the Talonflame or having a flying type out for you to target once you bring Groudon in. Or you just switch out, which kinda defeats the purpose but if their gameplan is to not attack talonflame you're essentially getting a free switch.
Ignoring PCs (which vary greatly in quality) Tflame has more CP than Dialga and Landorus-T, as well as abomasnow, palkia, and ditto, which are also in B-. It feels way more useful than the Pokemon around it, and B- seems about right.
Pretty sure the argument is it should be in B-. Whimsicott feels a little underrated too tbh, since prankster sunny day is a really cool niche. I'm not going to make that case since I haven't tested it, and I'm sure at times it feels like deal weight.
That being said the big reason I was testing talonflame was because it threatens grass types that are commonly used to beat Groudon/Kyogre. If you're relying on Venusaur to win the mirror match, you're in for a long day, which can't be said for any other fast TW user. Same for Ludicolo against Kyogre, although after testing that I felt like Tornadus was better in that teamslot if you have a tsareena on your team.
Speaking of which, Tornadus should probably move up quite a bit. It's currently in C- and just won a regional.
The other two Pokemon I think should move up are Pheromosa and Rayquaza. Rayquaza would obviously be exclusively paired with Kyogre, but can KO most Kyogre counters with flamethrower/arial ace. E-speed is a fantastic move on top of that. It also can support Kyogre with tailwind. I'm not 100% sold on it but it has better results than any of the Pokemon around it. I feel like C+ is appropriate for it.
Pheromosa is a Pokemon I've also seen popping up on Kyogre teams, including the one Ricardo used to top cut Frankfurt. It can outspeed Ludicolo in the rain, which is a cool niche. It also deals with other common counters such as Dialga/Ferrothorn, although losing your sash is questionable. With Tsareena/Lele everywhere you can avoid priority and while getting it requires a slow Fake Out or sacrificing something, it's not as susceptible to priority. The Tsareena pairing is particularly potent since you can feint + HJK to guarantee it comes off (90% of the time). In a meta where some of your Pokemon are going to be for exactly one matchup, Pheromosa is great at patching up the Kyogre mirror.
Finally, some Pokemon I think should drop:
Excadrill - it does literally nothing right now and has 0 CP. It's unviable.
Necrozma-DW - it's not terrible, per se, but it's outclassed in every respect by Lunala
Giratina-O - what does this thing even do? I guess you switch in on Groudon and Ogre but then you don't do anything. Maybe someone else can make a case for it not being a waste of a restricted slot?
Oranguru - gets one-shot by too much stuff to be a reliable TR setter. I guess it's not terrible once you get set up but it's only niche over Bronzong is not getting one-shot by lunala and not getting Faked out. but if you partner can get Faked Out, it's not really doing much. given that incineroar is everywhere and everyone's restricted already does a ton to it, I'm not convinced it should be used. Also it has 0 CP, which is remarkable given how many bad Pokemon have CP.
Tyranitar - unless you're AV you can't come in on Ogre, and you can't come in on groudon either way. Not to mention Xerneas bodies you as well. Also Solgaleo/DM outspeed and KO you. I'm just not sure what this is supposed to come in on, and if it does switch in it doesn't really put any offensive pressure on most things.
I too have seen a lot of Phero and Ray, enough to entirely relate to these remarks. I can agree with everything else except for my true love, Giratina-O.
Giratina-O is absolutely slept on as an anti meta threat. I am not at a point where I will be revealing my calculations with Giratina-o but I can confirm as the only restricted I've used on all of my teams this season, it has a role that has yet to be abused (which of course I intend to do >:))
I also greatly appreciate seeing this; this helps me to do the thing I do on an almost bi weekly basis by eye and puts it into a much cleaner format. I will be going through this tomorrow morning October 11th, to do a large update. If nobody has responded by this post I will simply update through this one. That chart is so thorough and is very impressive so many thanks. One thing to note is currently the list orders based on Tiers, than Alphabetically whereas in your list it shows a variance as a result of their name placing within the list. I can reorganize the lists to reflect that style of organization but I think generally it's been fine alphabetically. Anyone say otherwise?So I thought it would be useful to have the CP that each Pokemon has earned next to their ranking so I compiled the information from vgcstats.com in to a spreadsheet. I also took the mean and median CP for the Pokemon in each tier and for the most part there is a downward trend between ranks as you'd hope. I also calculated the % deviation of the CP earned for each pokemon compared to the average CP earned by mons in their rank. italicised the restricteds (not sure if cosmog is restricted, I assume it is?) as competing for a restricted slot really should affect a mon's viability. On the right hand side I have reordered the table in order of CP earned, in the same order as is listed on vgcstats.com to get a better picture.
https://docs.google.com/spreadsheets/d/1DZY4bKpqizeLjI9ZwuMUUYo4gp5vLstx2nCBVaPkKh8/edit?usp=sharing
So at first glance the Pokemon that deviate the greatest from their average viability ranking seem to be:
Bronzong (-)
Arcanine (-)
Drifblim (-)
Heatran (+)
Raichu (-)
Tsareena (+)
Abomasnow (-)
Tapu Bulu (+)
Mewtwo (-)
Necrozma-DW (-)
Oranguru (-)
Whimsicott (+)
Zygarde (+)
Clefairy (+)
Klefki (-)
Kyurem-B (-)
Kyurem-W (-)
Lugia (-)
Nihilego (+)
Porygon-2 (-)
Togedemaru (+)
Tyranitar (-)
Excadrill (-)
Cresselia (-)
Giratina (-)
Rotom-W (-)
Scrafty (+)
Thundurus-I (-)
Tornadus-I (+)
Everything in D tier both up and down
And for mons that are unranked I just chose an arbitrary cut off point of 90 CP for mons which should be ranked somewhere which are:
Salazzle
Gengar
Aegislash
Heliolisk
Victreebel
Lumineon
Sableye
Togekiss
Blaziken
Volcarona
I think these Pokemon should be the one's that we focus on discussing. I don't necessarily agree with all of the changes I've suggested, I just think they should help direct the discussion.
The worst offenders I would say are the following:
Tornadus
Clefairy
Salazzle
Arcanine
Abomasnow
Nihilego
Scrafty
Pheromosa
Lurantis
Gengar
Aegislash
Heliolisk
Victreebel
And of course all of the ranked Pokemon that haven't earned any CP, particularly the ones in the C tier.