_variables.less not overriding anything

I was under the impression that I could set @font-family-base and @headings-font-family, and basically any or all of the bootstrap typographic mixins in the _variables.less file supplied in Roots 7.x.x.

However, it does not override the font styles. Nor does editing the original variables.less in the /vendor/ directory. For example, I cannot get any @headings-font-family to stick, because there is a font-family: inherit set by default.

Changing the @font-family-base has zero affect on this, which is really frustrating me for the last hour - because it says in the markup, as well as on getbootstrap.com - that this style is inherited from the @font-family-base. Why would changing it have no affect?

Anyone have any idea how the hell I can make use of the builtin bootstrap mixins with this theme?

Are you recompiling with Grunt afterwards?

Ofcousrse. I am using grunt dev, but have tried everything. grunt less, grunt build. Could you give it a test yourself? It would help a lot knowing someone else tested the font styling mixins and shared success or failure.

EDIT: I should note that I see the styles I added being loaded, but they are over-written. Using the developer tools plugin, I have to disable (uncheck) the font-family: inherit property as well as the default font-family: "Helvetica Neue",Helvetica,Arial,sans-seriffor the body - to get my custom styling to show.

UPDATE: Just realized it was a third party plugin that was including an entire instance of bootstrap.min.css (stock download) without any prefixing. Apologies for the post- My frustration level was high.