Hello again Yaphet,
Spotlight is difficult to test and not at all reliable. If I manually create a scenario to test what you describe, then it works as you would expect. It does search by both contents and file names and prioritizes the file name. But I have never seen it work like that in the real world. If I actually don't know where the file is or what it is named, then I get back 100,000 results. In most cases, the file I want is in a folder that Spotlight does not search at all.
Spotlight and Finder are completely different things. Spotlight is the search technology used to search for pretty much anything on the disk. It is also responsible for for categorizing files into 20% music, 10% backups, 10% movies, 10% images, 10% apps, and 80% other.
I see your point about the SEO. The only time I see files named with dashes is when an alternative, like ":", "/", or "." is unacceptable for some technical reason. Usually files with dashes are fine, as long as the file doesn't start with a dash. Don't ever do that. Technically, there is nothing wrong with spaces, but you have to hope that every single script that is going to process your file has the correct logic for handling spaces. They do use the correct logic about 80% of the time.
