I work for an email marketing company and we use a propriety software to make our HTML emails. It's very old and definitely not a coder's dream. Unfortunately, getting new software is not an a quick or simple option since it's so deeply embedded in our system.
When making an email, I mainly code by hand and have relied on font stacks to give me some freedom with font faces. Other people who aren't so well-versed in code will use our propriety software's GUI to try to accomplish the same thing. When they work in the "build" view (instead of code view) and they copy and paste text, the styles of the text is copied with it, but it only keeps the first font in my font stack. So when they paste it, it will only paste the preferable font face and no fallbacks.
When someone copies this:
<span style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 14px; color: #333333">Hello</span>
<span style="font-family: 'Helvetica Neue'; font-size: 14px; color: #333333">Hello</span>
No, it will not. CSS inheritance does not work that way.
Suppose you have e.g.
<div style="font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;"> <span style="font-family: 'Helvetica Neue'">Hello</span> </div>
font-family property of the
span element has a value set. It does not matter that this value has no effect in most computers (which do not have Helvetica Neue). It's the value, and it is used. Since the element has a value assigned to the property, it cannot inherit it.
This means that the user agent’s own fallback mechanisms will be used when the font specified in the
font-family is not available. Basically, its default font (usually Times New Roman in web browsers) will be used.