Hi Ben2000,
I've typed up a response a few times in answer to your post, only to delete it, mostly because I'm only somewhat sure of where your misunderstanding is, and every time I type a response it went off in a direction that may have made your misunderstanding worse. Instead, I'm going to keep this brief, let you respond, and we can go from there.
First, watch the video below by flight-club. It gives an excellent description of how things work, although you may have to watch the video from 3:34 to 4:12 a few times because the author does not animate the pitot blockage description in the same way she animated the first part of the video.
Second, whether by accident or not, you mistyped the acronym. You have typed it to show a pitot blockage always underreading (PUD and PUC). The way you have it written it should be SOD-PUD-SUC-POC, although I've mostly seen it written as PUDSUC POCSOD. Ultimately, it doesn't matter how it's written if you remember the basic principles come exam time.
Third,(and this is where I think your misunderstanding may come from)
the acronym only applies to the airspeed indicator. By adding the altimeter and vertical speed indicator in the static block part of your post, you are confusing the issue. The acronym only applies to the airspeed indicator because it is the only pressure instrument that will be affected by a pitot or static blockage. As all other pressure instruments are supplied static information only, they cannot over-read or under-read in the same manner that the airspeed indicator will. With the altimeter and vertical speed indicator, there is either a change in static pressure or their isn't, so they can only ever show a change in altitude or vertical speed, or not.
This is normally where I would add a bunch of paragraphs to explain the information, but I'll let you respond first just in case you've had a light-bulb moment.