For the sake of other people struggling with the same issue I'll post the same solution I sent to Jen through e-mail here as well:
I'm afraid there is no "native" solution in XPression for what you're trying to do.
It's true that in XPression you can only create soft blended gradients. But it doesn't mean you can't use hard edged gradients :-)
In this case you'll have to create the gradient you want to use, in Photoshop and you'll have to import it as a material inside XPression.
Next you'll have to select the text and then double-click on the gradientmaterial you imported to apply that material to that text.
That should solve your problem.
There are however a few remarks when you want to use this workaround:
First, the material will be applied to each letter of the word individually. So if you're trying to create a gradient which is slighly tilted across an entire word, you're in trouble.
Second, I've noticed that if you're filling in the text dynamically through software or datalinq the material is not always assigned automatically.
However, in your case the gradient is a straight line so it shouldn't cause you too much trouble.
I hope this helps!
Best regards,
Kenneth
#XPression