Comcast will only bump some customers up to its fastest broadband connectivity if they subscribe to its cable television service.

The American telco'n'telly giant last week promised to increase people's bandwidth in a handful of US markets – Houston, Oregon, and south west Washington – provided they sign up for cable TV.

How much of a boost will depend on their existing plan. Comcast said customers who pay for 60Mbps will be upgraded to up to 150Mbps, while those on 150Mbps will move to 250Mbps, and those on 250Mbps will get boosted to either 400Mbps or 1Gbps service. Not too shabby, provided you don't smash into a monthly download limit.

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"We're very focused on providing a great customer experience by making our technology products easy to get and simple to use," Comcast Houston region senior VP Ralph Martinez said of the rollout in Texas.

"There's nothing simpler and easier than fulfilling our customers' need for speed to give them what they want, when they want it."

There is that one catch, though. In order to get the "free" speed bump, punters must subscribe to Comcast's paid-for TV service. In other words, if you're a cord-cutter who has canceled your Comcast TV service in favor of streaming-telly websites, you won't be able to get this latest "free" speed boost.

The move comes as Comcast continues to look for ways to slow the migration of folks away from its cable TV service. Though the overall cable business at Comcast continues to grow, most of that is due to its internet service. Last quarter – the three months to March 31 – the cable giant said it lost around 93,000 cable video (aka TV) subscribers compared to the same period last year.

On the one hand, you can see this offer as paying for faster broadband with "free" albeit unwanted cable TV on the side. On the other hand, you can see it as shelling out for Comcast's telly service just to get faster internet. It really depends on how much you want cable TV, and how far you're willing to go to get stupid-fast broadband.

Regardless, the move will no doubt cause more uneasiness among those skeptical of Comcast's commitment to preserving open internet ideals in the absence of any net neutrality protections by the FCC.

While the bundling requirement is not a net neutrality violation, it will be seen as a sign that Comcast is willing to cap service quality for customers who don't agree to cough up for other products – and could pave the way for further measures by Comcast to exploit its position as the sole high-speed broadband internet option in many markets to further gain an advantage over competing services.

Monopolies gonna monopolize, in other words. ®