In the hands of a smart player, G&W is a godsend in teams.
G&W can be an amazing stock tank with bucket braking and "planking" / running away. G&W can also dish out a lot of damage really really fast. Most, if not all, teams matches I've played, I have done more damage than my teammate. It really all depends on the playstyle the user chooses to have. If he keeps rushing in, he will get a huge DPS score, but not do so well at Stock Tanking. If he stays back, runs, and UpBs a lot, he'll manage to Stock Tank like none-other but won't do nearly as much damage as he could have.
Powerful Qualities that make G&W so amazing in teams:
- UpB - G&W has a fast start-up, invincible/high-priority, hard to punish, GTFO move... UpB. This move allows G&W to be so versatile it's ridiculous; it's power is completely underrated in teams. Have you ever tried using UpB literally every other move in teams? It's so fast and hard to punish, especially with a small mix-up here and there. Believe it or not, this is G&W's most important move in teams... well second to his ******** killing power.
- Windboxes - G&W, unlike most other characters, has two moves that create windboxes really fast. This allows G&W to do what most characters could only dream of, saving their teammates from death at any percent. Sure all characters can footstool but that's pretty hard to do and occurs rarely even among pros. However, with G&W's uair you can save a teammate several feet above you! This allows G&W to sit back, not fight, and let his teammate safely throw out attacks without a fear of dieing horizontally.
- Move Decay - G&W, unlike most characters, does not suffer from move decay in teams. Because of how easier it is to just UpB OoS when standing next to someone (UpB's windbox restores decay) without getting punished AND how easy it is to Uair anyone (including your teammate) that gets above you, G&W is able to restore his decay in a matter of seconds. It happens so fast since there are four people on the screen, you don't even realize it. G&W's kill moves can be refreshed whenever you like, so spamming them / using them to rack up damage is actually an OK strategy.
- Judgment - G&W is one of the few characters that has a OHKO (One-Hit KO) move. Sure it may not be the easiest to hit with, but that doesn't matter in teams. In teams a grab by your teammate on the opponent = death. Most characters when partnered with G&W have a grab option that guarantees a hit with a Judgment. MK = Dthrow, Uthrow. Snake = Uthrow, GrabRelease. Wario = Fthrow, Dthrow. If anything they can just hold them there. If you don't think this is a viable quality, ask Dojo. He can testify to it's power.
- Bucket - Lol wtf is this? You are telling me they created a character that when paired with certain characters from the cast it now has a hidden OHKO move that comes out on frame 2? Silly G&W, why are you so broken. Anyway, you've heard of the G&W + ZSS team? Yeah it's powerful. G&W can do the same thing with quite a few other characters too like Lucario, Pikachu, Luigi, Zelda, Pit, Ness, Lucas, Kirby, ROB. They all give G&W a bucket so powerful it KOs from 0% - 30%. This quality isn't as amazing as the others, but it's nothing to just skim over. There's only like 2 other characters in the game that benefit from character pairs in a similar way.
Videos:
UTD Zac
http://www.youtube.com/watch?v=aa5wTCMAt2g UTDZac DMG vs Dphat LeeMartin
http://www.youtube.com/watch?v=8WdJ79GH-9k UTDZac UltimateRazer vs Bassem KosMos
http://www.youtube.com/watch?v=Wcmkpv5BpaU UTDZac UltimateRazer vs Joker Razor
http://www.youtube.com/watch?v=Z5xCi1gxmnc UTDZac DMG vs UltimateRazer Gnes
http://www.youtube.com/watch?v=hQEF_6MjiYU UTDZac DMG vs UltimateRazer Gnes (Rainbow Cruise)
http://www.youtube.com/watch?v=80bmur04Zx8 UTDZac DMG vs Dojo PhantomX
http://www.youtube.com/watch?v=GhV9v5_LK7s UTDZac Sethlon vs Bwett Fogo (Bonus)
http://www.youtube.com/watch?v=tUe8u2sKLn0 UTDZac Dphat vs Bwett Shuz (Bonus)
http://www.youtube.com/watch?v=8WdJ79GH-9k UTDZac UltimateRazer vs Bassem KosMos
http://www.youtube.com/watch?v=Wcmkpv5BpaU UTDZac UltimateRazer vs Joker Razor
http://www.youtube.com/watch?v=Z5xCi1gxmnc UTDZac DMG vs UltimateRazer Gnes
http://www.youtube.com/watch?v=hQEF_6MjiYU UTDZac DMG vs UltimateRazer Gnes (Rainbow Cruise)
http://www.youtube.com/watch?v=80bmur04Zx8 UTDZac DMG vs Dojo PhantomX
http://www.youtube.com/watch?v=GhV9v5_LK7s UTDZac Sethlon vs Bwett Fogo (Bonus)
http://www.youtube.com/watch?v=tUe8u2sKLn0 UTDZac Dphat vs Bwett Shuz (Bonus)
FuriousDuffman
http://www.youtube.com/watch?v=rir--Sta19M FuriousDuffman Dekar vs Roni Sethlon
Hylian
http://www.youtube.com/watch?v=MLGodaQ0MVc Hylian Lain vs LeeMartin Dphat
Lou
http://www.youtube.com/watch?v=PKBDcQf506M Lou YBM vs Nope Capem
http://www.youtube.com/watch?v=JOUs5VG85uk Lou YBM vs Nope Capem
http://www.youtube.com/watch?v=katO_7DujM8 Lou YBM vs AlphaZealot Lain
http://www.youtube.com/watch?v=JOUs5VG85uk Lou YBM vs Nope Capem
http://www.youtube.com/watch?v=katO_7DujM8 Lou YBM vs AlphaZealot Lain
Summary:
G&W is like a Swiss Army Knife for teams. He's whatever you want in any situation. He can easily adapt to bad scenarios by changing playstyles in the middle of a game. He's a fragile character, no doubt, but in the right hands of a smart player he becomes like a balloon in a wind tunnel.