{{!-- Generates request for lineItems --}}
{{#each model.lineItems as |item|}}
	{{item.name}}
{{/each}}

{{!-- Doesn't generate request and throws error
{{#each-in (group-by "name" model.lineItems) as |name lineItems|}}
  <h1>{{name}} Artists</h1>
  
  <ul>
    {{#each lineItems as |item|}}
      <li>{{item.name}}</li>
    {{/each}}
  </ul>
{{/each-in}}
--}}