Love the link

If it takes a man an hour to dig a hole, how long will it take two men to dig half a hole?

How long it will take to design a template depends entirely on how skilled you are, and where you draw the line as being "complete". Talk to any painter, most of their artwork is not "finished", there's always something that can be added, removed or changed.

I usually start with a prebuilt template these days as you can pick up one relatively cheap (and dirt cheap in some cases). Then build and "kit-bash" and modify to your hearts content. When I design cookie cutter web sites for people, I can be done with a 5 page site in less than 3 hours when they provide the text and images they want online, up to 5 hours if they only provide a logo and text, and it could be DAYS if they only provide a logo with nothing else.