Would anyone consider doing a large shop
sign from a business card?
I probably would not. The result would not make for an effective primary
sign because most business cards have far too much information on them that isn't necessary on a larger
sign. If you blow up a business card to a 4'x8'
sign, it's going to look like a big ugly business card and not a
sign.
It's okay to use the pertinent information from the card to design a
sign but that's all its good for. Business cards and primary
signs, serve two different purposes. A business card can list a lot of crap but the main
sign needs to be straight to the point. It should be simple and legible through the use of good fonts and appropriate color choices and intelligent design.