This hasn’t been changed since we implemented (and enabled the switch to turn it on and off). I think there’s likely some skew here on how many people have it turned on vs turned off - just due to the nature of the forum.
That said, there really isn’t too much to this feature. With fast live TV startup enabled, the Tablo sends fewer segments to its devices and starts the stream earlier. For some networks and devices, this buffer is too small, and can lead to buffering - in some cases, it never recovers.
With the feature turned off, the Tablo waits for more segments before hitting ‘play’ on the device. Bigger buffer, less wait time.
It cannot JUST be a network issue because I have a rock solid LAN setup, All 1000 Mbps modems, router (newest Nighthawk), switches. Everything is CAT 6 cabled with no wireless connections, and 50 up/down service. If that cant run fast nothing can.
This is one of the more common misconceptions we see. The 1000Mbps is an advertised, or max speed, and the 50Mbps up/down service is referencing your upload/download speed to the Internet. These don't represent the LAN speed. There used to be some really great (and easy to use) tools to accurately test your LAN speed from one IP to the other. But we've recently seen a lot of these apps/services go extinct or have their prices driven up to the point where we can't recommend them.
In all fairness, though - the LAN speed should be (or typically is) faster. And even then - if you're on all wired connections, it's even weirder that you'd see buffering. I can't explain that. I'd lean towards the max bitrate of the Roku being exceeded in most cases, but I can't say that for sure. Depending on how far you want to investigate this, we could take a look at some measuring tools to see the speed you're actively getting.