Blaziken got speed boost this generation through Dream World. Using Protect / Swords Dance / Flare Blitz / Close Combat under the sun made it basically onstoppable. I believe it OHKO'd Gyarados in the sun with a +1 Flare Blitz. That's pretty amazing. So he was banned entirely since smogon doesn't want to make "complex" bans and create multiple standards for other pokemon. If they just banned Speed Boost on Blaziken, why not ban it on other things like Sharpedo, Ninjask, etc.?