Team Preview
image credited to Zebraiken

image credited to Zebraiken
Team preview was one of the most controversial introductions to the 5th Generation. "It would ruin the surprise factor in Pokemon battles!"; "There are no such thing as leads now!"; "No more scouting, either!"; "Naaw guys, it's okay because both teams are still on equal playing ground!" The mechanics of Team Preview work just like this: in-game, a selection screen pops up showing both teams and the ability to set the order in which your Pokemon are to appear in battle. On Pokemon Online, the screen is a bit more friendly, with both teams shown in one line and the default order being that of your team in the Team Builder window. You can arrange the Pokemon in any order just by clicking on the sprite representing that Pokemon and clicking on its new position.
The most important implication here is that you can choose your lead Pokemon based on the information you can gather just by looking at your opponent's team! Naturally, people predicted that using dedicated "suicide" leads such as Azelf or Aerodactyl, who were so popular in DPP as a means of almost guaranteeing Stealth Rock, would be less effective. You could now see your opponent's team and see which lead you are using and use the appropriate check as their lead. The abundance of Politoed and Ninetales as weather starters threw a monkey wrench in the plans of Tyranitar and Hippowdon, formerly the only instant weather starters in OU.
Have these early hypotheses remained true? In what ways have Team Preview benefited or hindered the Pokemon experience? How has it affected either your caution or your recklessness over the course of the match? What leads have become common?
One of the most common and dangerous leads in OU has been Rotom-W.
Rotom-W can run a variety of dangerous sets, from Choice Scarf to Choice Specs to bulky support. The danger here is that Rotom-W can fit Volt Switch very nicely on on any of its common sets even if it's not being used as a lead. The very sight of this Pokemon can make you think twice before sending out your weather starter, especially but not limited to, if they have a weather starter of their own. Consider the following scenario:
You are running Politoed as your weather starter. You see that your opponent has no weather starter of their own, so you are safe to get your weather immediately. But wait one second... Your opponent has a Rotom-W, who is naturally faster than Politoed and poses a threat with Thunderbolt or Volt Switch. Your opponent, knowing that you have control of the weather from the get-go, will likely predict your Politoed lead and send out their Rotom-W. The battle starts and as you may have expected, Politoed and Rotom-W face off. Being the master of the type chart that you are, you switch to Ferrothorn, who sponges both of Rotom-W's STAB attacks with its resistances and excellent Special Attack. Wait, wait... you see that they have a Magnezone! Gastrodon would be a wiser choice, being immune to both of Rotom-W's STABs and potentially getting a Special Attack boost from an overpredicted Hydro Pump. In either case, you hope to God they don't Trick you a Choice Scarf.
Do predicaments like these affect your team building? Gastrodon is a great Pokemon anyways, but would you feel it absolutely necessary to use one to take advantage of this very situation? Discuss!
The most important implication here is that you can choose your lead Pokemon based on the information you can gather just by looking at your opponent's team! Naturally, people predicted that using dedicated "suicide" leads such as Azelf or Aerodactyl, who were so popular in DPP as a means of almost guaranteeing Stealth Rock, would be less effective. You could now see your opponent's team and see which lead you are using and use the appropriate check as their lead. The abundance of Politoed and Ninetales as weather starters threw a monkey wrench in the plans of Tyranitar and Hippowdon, formerly the only instant weather starters in OU.
Have these early hypotheses remained true? In what ways have Team Preview benefited or hindered the Pokemon experience? How has it affected either your caution or your recklessness over the course of the match? What leads have become common?
One of the most common and dangerous leads in OU has been Rotom-W.

Rotom-W can run a variety of dangerous sets, from Choice Scarf to Choice Specs to bulky support. The danger here is that Rotom-W can fit Volt Switch very nicely on on any of its common sets even if it's not being used as a lead. The very sight of this Pokemon can make you think twice before sending out your weather starter, especially but not limited to, if they have a weather starter of their own. Consider the following scenario:
You are running Politoed as your weather starter. You see that your opponent has no weather starter of their own, so you are safe to get your weather immediately. But wait one second... Your opponent has a Rotom-W, who is naturally faster than Politoed and poses a threat with Thunderbolt or Volt Switch. Your opponent, knowing that you have control of the weather from the get-go, will likely predict your Politoed lead and send out their Rotom-W. The battle starts and as you may have expected, Politoed and Rotom-W face off. Being the master of the type chart that you are, you switch to Ferrothorn, who sponges both of Rotom-W's STAB attacks with its resistances and excellent Special Attack. Wait, wait... you see that they have a Magnezone! Gastrodon would be a wiser choice, being immune to both of Rotom-W's STABs and potentially getting a Special Attack boost from an overpredicted Hydro Pump. In either case, you hope to God they don't Trick you a Choice Scarf.
Do predicaments like these affect your team building? Gastrodon is a great Pokemon anyways, but would you feel it absolutely necessary to use one to take advantage of this very situation? Discuss!