Right before Christmas, YouTube publicly called out T-Mobile’s Binge On streaming program for allegedly slowing down all video content, potentially in violation of new federal “net neutrality” rules. Now T-Mobile counters YouTube’s argument by claiming that it’s just trying to provide users with speeds that are appropriate for use on mobile networks.

To back up a couple months, T-Mo introduced Binge On back in November, with the headlining idea being that users’ data plans would not be charged for accessing certain participating video streaming services.

What wasn’t screamed out in that announcement was that Binge On video doesn’t stream at full resolution. Furthermore, it isn’t just the videos from Binge On participants — like Netflix, HBO Go, Hulu, and Sling — that gets this treatment. T-Mobile is also capping resolution on services that don’t participate in Binge On, like YouTube.

“Reducing data charges can be good for users, but it doesn’t justify throttling all video services, especially without explicit user consent,” a YouTube rep said last month.

You may not have noticed, but the YouTube rep’s use of the term “throttling” is incredibly problematic for T-Mobile.

See, the recently enacted neutrality rules explicitly prohibit broadband providers — including wireless companies — from throttling access to “particular classes of content, applications, or services.”

It’s perfectly fine for the content company to push lower-resolution video to mobile devices, or to give customers that option of receiving streams that aren’t full-quality, but if a broadband provider is monkeying around to deliberately slow down that stream, a line may be crossed.

Speaking to DSLreports.com, a rep for T-Mobile contends that the company is not doing anything wrong with YouTube content.

“Using the term ‘throttle’ is misleading,” explains the T-Mo rep. “We aren’t slowing down YouTube or any other site. In fact, because video is optimized for mobile devices, streaming from these sites should be just as fast, if not faster than before. A better phrase is ‘mobile optimized’ or a less flattering ‘downgraded’ is also accurate.”

This is where things get interesting. T-Mobile argues that it’s not throttling because the videos stream “just as fast, if not faster.”

If you were talking about website loading times, then there’s really no problem with that argument, but when talking about streaming video, it’s often not simply a question of how quickly something streams. The FCC may eventually have to settle the question of whether it’s okay for wireless providers to downgrade video for optimal network performance, or whether that practice counts as throttling.

Want more consumer news? Visit our parent organization, Consumer Reports, for the latest on scams, recalls, and other consumer issues.