Solving the 1 Route 2 Controllers problem

1bird2stones.php

<?php
// Given you want to perform one of two or more actions with a single url.
//
// in Config/routes.php

Router::connect('/:username/:action', array('controller' => 'users', 'action' => 'userOrShop'));

// Your UsersController.php might look something like this then.
class UsersController extends AppController {
  
  public function userOrShop() {
    // Do whatever you need to do to determine if the requested user is a 
    // "shop" or just a user here.
    
    if ($this->User->isShop()) {
      return $this->_doShopThing();
    }
    
    return $this->_doUserThing();
  }
  
  protected function _doShopThing() {
    // This is where your regular controller logic would go for when the user
    // is a shop like "BobsShop.
  }
  
  protected function _doUserThing() {
    // This is where your logic for a username of "Bob" would go.
  }
}