unbloating Rails' respond_to scaffolding

respond_to.rb

# why does Rails generate this...

  def index
    @users = User.all
    respond_to do |format|
      format.html # index.html.erb
      format.json { render json: @users }
    end
  end

# ...and not something like this?

  def index
    @users = User.all
    case params[:format]
      when 'html'
        # index.html.erb
      when 'json'
        render json: @users
      end
    end
  end

# ...or -- because 'html' is a no-op -- this?

  def index
    @users = User.all
    render json: @users if params[:format] == "json"
  end

# or (assuming a new method named "format_as?")

  def index
    @users = User.all
    render json: @users if format_as?(:json)
  end 

# The whole "respond_to" thing makes learning and using Rails harder 
# than it needs to be. It smells like it was written by someone who
# just learned about blocks and really wanted an excuse to use them.

# TL;DR: Rails Hates Ruby