I get where less could be used, but doing this (which doesn't work):
<div class="fixed-width(150px)" ></div>
...seems like it makes more sense than the offered example of:
<div class="fixed-width" ></div>
Is there an easy way to accomplish this I'm missing?
No. LESS compiles the CSS file only, not the inline CSS as well. You'd have to write an improved parser to generate the code you're already using.