Theoretical is the key word, Xbox 360 has a shader efficiency around 60%, and it's shader count is actually hindered to only 217gflops iirc, which means that you are only capable of extracting about 130gflops from the 360 per frame, at least without extreme care to GPU bottlenecks like low level cache and thread wave allocation.
The dock help performance, so it fits the patent.
You should take into account that in any case games will be aimed to the undocked power, not to an eventual optional accessory, so in any case even if a new dock will give more power if would be used for better resolution and framerate and maybe some effects, nothing more.
Let's stop with this myth, flops are flops, there aren't maxwell flops or whatever flops, they are like kilometers/hours(or miles/hours), a 2017 car can be more efficent, being more comfortable, less polluting etc than a 80s car, but if they do the same km/h then they do the same km/h, period.
Gflops are the number of floating point operations per second, why they are important? Because everything is a floating point in 3d, a 3d model of a big game is made of dozen or hundreds of thousands vertices that have at very minimum 3 floats for the position and 2 floats for the texture coordinates(but more realistically they have many more floats of data), also translation and rotation data are other 3 floats each that have to be multiplied with every single vertex and so on.
You can do floating point operations in a way or another but in the end is the gflops that count.
If games on a newer gpu look better than games on a older gpu with comparable gflops is probably because of newer shaders and the help of more ram, more powerful newer cpu and so on.
VLIW5 in Wii U is capable of about 80% efficiency, and so it's 176gflops is only capable of about 140gflops per frame, again you can painstakingly extract a bit more, but threads will allocate through the architecture and run into issues where only 4 of the 5 available stream processors can process data.
Maxwell architecture has over 96% efficiency, so that 196 gflops in handheld mode is 188gflops or 377gflops when docked. since 2005, these processors have gotten better at handling effects more efficiently as well, and you shouldn't directly compare gflop numbers because it just doesn't work that way. This is why generally Nvidia gflops will perform 4/3 better than GCN, this is without heavy Async compute engine utilization, but that is only recently wide spread and hasn't been a focus for Nvidia's drivers where they could gain back ground here.
We also haven't touched on fp16, as many graphic operations do not need 32bit values, this is a game by game basis, but with some developers reporting a 70% utilization in their own games, it is safe to say that it can certainly gain ground as developers get more and more use to writing code with 16bit floating point values in mind.