I'm a bit of tech junkie and I can only speculate as to why there is a stutter on Xfinity Streaming service via. the now included subscription services such as Netflix and Prime.
Comcast knew they were getting slammed by cable cutters opting to go with streaming services such as the main two listed above.
They increased their price on Internet services / packages and then made a deal with Netflix and Amazon to allow streaming their content instead of using : Smart TV apps or USB sticks.
This allows them to monitor your viewing habbits and suggest content all while keeping you on COMCAST services regardless of what content you watch. The down side is Netflix and streaming services are being piggy backed through Comcast via. their main server. Instead of having a built in app like Smart TV's you basically are piping into a shared server for all Comcast users in the marketed area. This will cause lag / latency. If you want to watch Netflix do it from a game console , smart tv, media player. Xfinity is a watered down version.
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