Basically, I'm just glad to see people being able to talk customers out of putting hours and address stuff on their main sign. The front door is where it belongs.
Can't tell ya how many times I've parked the car in a parking lot walked over and as someone mentioned, yanked on the front door to find out they were closed. For me, it's very helpful knowing their actual hours and possibly not in at all on a Tuesday or something. As for seeing from 18' away, that's a little much, but understandable for certain situations. The average eye can see 3/4" lettering at about 35', so most anything should be legible, unless you're putting the Gettysburg address on it.
As for bulking up the type style..... remember, when you beef up the strokes, you're also making the centers/middles of letters smaller, which also can make for difficulty when viewing from any kinda distance. Just picking a fat style doesn't always cut it. You must determine how much things will close up to the point of being illegible. Going with the extra bold or black choices are usually good for all caps with lotsa kerning space. Normal reading is usually upper and lower case and needs some attention. Again, as mentioned, being sign makers, we are trying to make the most mundane things have eye appeal without going overboard. So yes, even a little hours display sign in a window can take a little time to create. In the end, it's worth it.