What's wrong with this setup? The cable co's use it, and in most instance it works well. The issues occur when there's over saturation - not enough blades to handle the load. Speeds go down, noise goes up, speeds go down more so... Perpetual cycle.
In fact, I recently had an issue with my cable provider where during prime time hours, speeds would drop 25-40% or more. At first look it would appear to be a capacity issue, but in my talks with the head of local operations, that wasn't the case. Plenty of capacity in this area to go around. Turned out during prime time, due to additional load, a failing card/blade (not the one I was connected to) was generating noise, which ultimately was causing my issues. They replaced the offending part, returning my speeds back to 20mbps at all times of the day.
Bottom line, who cares what method they use to increase speeds and bandwidth, so long as it works and is consistent.
Evo 4G LTE HW v003
Evo 4G Retired