It's possible to rush to the Enriched ores tech before unlocking Titanium processing. I didn't want to gate enrichment on Titanium processing, and I also thought it was strange to unlock Enriched titanium prior to unlocking Titanium processing, so I added the tech. I realized I didn't need it for tungsten, since that is needed to get to blue science.
Also I just noticed I need to fix a recipe icon in enriched tungsten smelting :)