Seems the 737 club took over. As I recall it was a320 question. At high altitude, max CLB, MCT and TO are the same limit. However selecting MCT or TOGA will react much faster then the autothrust on a speed-decay.
On a 320 you are also lucky that the high speed limits are more generous and in general the margin between low and highspeed is much bigger then on a 737.
I also loved that statement that take-off thrust can never be selected in any other phase then take-off.
You guys need to get out more instead of watching the SAT. There is also a difference between optimum, max recommended and max cruise altitude.
Max recommended really is not that dramatic, and you can only plan for what you know. Our company downloads winds and temperature for the entire route into the fmgs, so yes the fmgs can foresee what will happen in the future a long as it is forecast.