incrediBILL - 9:44 pm on Sep 30, 2012 (gmt 0)
You're talking apples and oranges, but the answer is yes, it should add a marginal improvement to W3 total cache.
The efficiency of W3 Total Cache is that it prebuilds page requests and stores the results so subsequent requests don't always trigger a complete SQL query to regenerate each time.
The combination of the 2 should be quite nice on a high volume site.
I've used the same basic script with some slight variations on a PHP site of mine to provide extensionless SE friendly URLs and it works really well.