If you have 8 AP, couldn't you do a full block and a full dodge?
Yes, and that's the problem. At 8 AP, doing a partial block and a partial dodge together costs the same or more than doing a full block or dodge.
Why? Because full Block and Full Dodge both have flat costs -- 4 AP each -- while partial block and dodge cost Concentration. So with 8 AP to spend, you can do one full Block and one full Dodge in the same round, and still be able to take an instantaneous action and move how you want, up to 2x pace (at a penalty to the full block+dodge of course).
But note that because Partial Block and Dodge don't have a flat cost, but instead cost Concentration, then when you are Hasted and have 8 AP, a partial Block and Dodge costs the same as a full block and Dodge, and the partials even have it worse: you still have to make a Mental Focus maneuver and can take no other action but movement at a Creep. This is, again, because partial block and dodge do not have a set cost, while full block and dodge do.
So essentially, without set cost for partial block and dodge, partial block and dodge paradoxically both effectively cost more and place additional constraints on your actions (you literally can't move as fast while doing a partial block/dodge) than a full Block/Dodge.
Hence, why I have changed their cost from Concentration to 2 AP.
