As far as I am aware, most controllers and inverters will limit based on the output current into the batteries. They could also limit based on the input current. The Classic can do this but that adjustment is mainly for micro-hydro so that the turbine doesn't bog down.
If a SCC/MPPT is "ALWAYS" at its limit, every day of the year, then I would call that an over-sized array for sure and power is more than likely being wasted. But then again, solar is cheap these days so maybe the charge controller or inverter should be over-designed. If a company is doing that just so it can be over-paneled, they would be shooting themselves in the foot so to speak.
boB