Auto-adjust text size for slide content

[axiomtutor]

I'm making a "presentation" which really is just going to be lectures for a math course. I'm really putting all the notes into the presentation. So although when giving a presentation you're not supposed to put too much text on a given slide, in this case I think it's appropriate for talking the students through long proofs and calculations. Therefore I often exceed the boundaries of the slide and need to adjust the text-size down.

However, I don't want to just set all the text size down, I like the big text to prominently show what I'm currently talking about. So I've been solving the problem with a custom-made .small CSS class, used in the following way:

<section>
	<section>
		<h2 class="fragment">Domain, range</h2>
		<ol>
		    <li class="fragment">
			For any relation $R$ we can define its <b>domain</b> to be \[dom(R) = \{x\in A| (\exists y)(xRy)\}\]
			Which is to say it is the set of all arguments.  However, we primarily are concerned with the domain of functions.
	    		</li>
		</ol>
	</section>
	<section>
		<h2 >Domain, range</h2>
		<ol>
			<li class="small">
				For any relation $R$ we can define its <b>domain</b> to be \[dom(R) = \{x\in A| (\exists y)(xRy)\}\]
				Which is to say it is the set of all arguments.  However, we primarily are concerned with the domain of functions.
			</li>
			<li class="fragment">
				The <b>image</b> is the set of all values,
				\[ im(R) = \{y\in B| (\exists x)(xRy)\} \]
				The book calls this the range, but this is likely outdated (although it may just be wrong).  The <b>range</b> is any set containing the image.  If $ran(R)$ is the range then this means \[im(R)\subseteq ran(R)\]
			</li>
		</ol>
	</section>
</section>

The effect is that using fragment reveals new text item-by-item, but when the screen fills up then I can click down and all the old text turns small, but the new text is large and has that wonderful fragment transition.

It's working great, but my only complaint is that it is very hard to manage and organize all this code. If I go back and change something I have to change it in many places. The source code is hard to read because it's so long and full of repeated text.

So as a feature request, I wonder if this would be easy to implement in a future version?

Or perhaps there's some better way to do it than what I've been doing so far?

Thanks for the great product!