Looks like we have different meaning for supports.
A ward bitch is just that, a ward bitch. Any hero can be a ward bitch, just some are better than others at the task.
A support is a healer/tanker/crowd controller/mobilizer/disabler.
A carry is the guy that deals the highest dps.
The terms carry/support are more for their ability to contribute with farm.
The best true supports can contribute greatly without any gold. It obviously scales, because some are in the middle.
Puck is a great example of a crowd controller/disabler, but is really weak when left at the #5 position. Necro falls in the same boat, but because of his single disable with a long CD, he doesn't fit in the professional meta. I would say he is a Tier 2 middle laner (after the main mids QoP, Puck, etc).