This macro does not render correctly if embedded inside of another user macro. To re-create the problem simply create a new user macro with no params, "rendered" body, and the following template:

1. 1. @noparams
      $!body

it looks like the rendering engine gets confused by a span tag

it converts from:

<div class="aui-message success shadowed information-macro">
<span class="aui-icon icon-success"></span>
<div class="message-content">
<p>How does a tip work?</p>
</div>
</div>
into

<div class="aui-message success shadowed information-macro">
<span class="aui-icon icon-success">
<div class="message-content">
<p>How does a tip work?</p></p>
</div>
</span></div>