code: public function removeBlock($spec)
  	{
  		if ($spec instanceof Block)
  			$spec = $spec->getKey();
  
  		if (is_string($spec)) {
  			if ($this->blocks[$spec]) {
  				unset($this->blocks[$spec]);
  			}
  		}
  	}
docs: Remove a block from the list
  @param $spec