Overclocked comes in because the intended MHz for the PSP processor was 222. Developers were allowed to set the CPU into overclock mode after a while.
Regardless of all this, the outcome is the same. MHz have no baring on true processor power readings, and cannot be used to measure potential emulation success. Due to the architecture of the DS and GBA, along with the added horse power, an official GBA emulator made for the DS would most likely run perfectly fine.
Feel free to return to the topic at hand.