There are three PLLs running at different speeds, 245, 960 and 800 unless I remember it wrong. In the frequency table you tell it what PLL it should use and what divider it should use. For example PLL0 (960MHz) with divider 2 makes the 480MHz speed. For the Skate and the Blade2 PLL2 is 800MHz and uses divider 1 (dividers are always set as (divider - 1) in the table.

Actually you should be able to overclock the skate and the Blade2 with just changing the frequency table by using PLL0 and divider 1 (0 in the table). That would create a 960MHz frequency and leaving the GPU clock (and all other clocks intact).

However, we want options, so what we can do is to change the speed of PLL2. The PLLs are configured by using multipliers and it can be configured up to 63*19200kHz. So what the code does is that for speeds above 787200kHz it modifies the multiplier of PLL2 and when it comes down to 787200 or lower it restores it's original value again. This is also why this way of overclocking affects the GPU. On the Blade and the V9 I know that the GPU is tied to the PLL2 as 3D speeds went down when CPU speed went up when I used PLL2 for overclocking. That is why the Blade and the V9 uses PLL0 instead. PLL0 on the other hand is connected to the camera so overclocking does underclock the camera and can cause some (acceptable) issues. Most likely the GPU is tied to PLL2 on the Skate and the Blade2 aswell but using a different divider and on the Skate and the Blade2 PLL2 starts on 800MHz so we have 50% to go. On the Blade and the V9 it starts at 1190MHz and we can only increase it from multiplier 62 to multplier 63 to get a tiny bit extra out of the GPU.

All needed changes is in acpuclock.c. CM7 also need some changes in cpufreq.c but for SetCPU that is not needed.

Look at the code starting at line 542 and 571 here:

https://github.com/TomGiordano/kernel_zte_blade/blob/2.6.35/arch/arm/mach-msm/acpuclock.c

That's the code that reprograms PLL2.