FlightPath...
This is from Canada's current TP 308 document - there are 3 pages I've uploaded.
First page shows that all maneuvers are based on airplanes flying by the speeds listed under paragraph 212 - this is applicable all times there are specific restrictions or minima for categories published (ie: spec vis departure, DA, MDA, circling, etc.)
As you know, TAS at altitude will be higher than IAS and that needs to be compensated for. Formulas published in the TP 308 document account for that.
Page 3 shows a very similar chart to the one you posted. This is Canada's guide to developing instrument procedures and this is what we follow. Essentially, protection areas are defined based on these speeds, which provides a margin of safety for aircraft operation.
I will emphasize that aircrews are to abide by the chart on page 1 to determine what category they are in based on their indicated speed at which they are carrying out the maneuver.
https://www.box.com/s/iwreiuzbt040jglkwhra
https://www.box.com/s/3htnrh8n6kvw389n3zw7
https://www.box.com/s/2frpd9y2ipb12lqma4x2
Edit:
What does the FAA use for determining category for specified visibility takeoffs?
I don't think you understood my question. A specified visibility takeoff is a visual climb over the airport for the initial departure, up to a specified altitude so as to clear obstacles. Usually a standard 1/2 departure will also be depicted but with a climb gradient in excess of 200'/NM. If you are unable to meet the required higher climb gradient, you have the option of departing while maintaining visual contact with the center of the aerodrome until a certain altitude that will permit a 200'/NM climb up to the minimum altitude for enroute operations. The required visibility in Canada for such a takeoff is: Cat A (1SM), B (1.5SM), C and D (2SM).
Does the US have such a thing?