Silver-Tiger said:
Given the already short battery life, it's probably to save energy. The PSP came with a 333 MHz CPU, yet devs could only use 222 MHz for whole two years after the release. Sony allowed the full use of the CPU in 2007: "The hardware was originally forced to run more slowly than it was capable of and most games ran at 222 MHz. However, with firmware update 3.50 on May 31, 2007, Sony removed this limit and allowed new games to run at a full 333 MHz." From Wikipedia. |
This is probably the main reason. The battery life already wasn't something to write home about, with devs using more power it will cause it to die out much quicker. This may improve graphics some (no, not by 25%), but most likely it will be used with games that use more of the HW to run them more quickly and smoothly.