Now, unless you're Carmack, you can't work alone. Take a look at the 2003 off the shelf titles and see if you have the time (to say the least) to write half of any popular game. Of course there are exceptions like GameBoy where you can probably do most of the work by yourself (excluding the artwork).
Whether that is PRO or not, I'll let you decide, but it's definately a professionally (not to mention socially and financially) viable approach.
Sure, as I said there are exceptions. As for myself, I have written games that were published in popular magazines in the mid to late 80s , at a time were you could do everything by yourself (does anyone remember Uridium, by Andrew Braybrook?)
UPDATE: Is there any trick involved for the quote thing to work?