Jay:
We built a couple of par-3 19th holes a few years back, at Stone Eagle and at Sebonack. They both fit into the terrain pretty well and took advantage of a cool green site that wouldn't work for the 18-hole routing. I had no problem with doing that. The one at Stone Eagle gets used a fair amount, the one at Sebonack less so, I think.
Those were clearly intended as "extra" holes. As for just building a 19-hole course where we intend you to play all 19 as part of the plan ... I'm not a big fan of that idea. I've seen similar things a couple of times, and it always comes across like the architect just couldn't make up his mind what to do.
I'd rather build a par-6 than do that.
The land for the hole at Black Mesa really made more sense as a par-6 anyway ... it was a very long stretch with no obvious green site. And you're still three holes away from the clubhouse, so breaking it into a short 5 and a par 3 doesn't help much, when you're going to end on a long par 4 for the 19th.
But, I've heard zero about that project for the past four years, so it sounds like the only way it's going to happen is if I'm going to go build it with my own money. And if I ever decide to do THAT, then you'll get to see a par-6.