I think Greg has been straightforward about why he doesn't do many VA blends -- they aren't his personal cup of tea, as a rule. He is a Latakia lover, first and foremost, so thats where he usually goes. Plus, I think both Union Square and Opening Night are the equal of anything Gawith puts on the market. That is just my opinion, though! I don't think it has as much to do with the base leaf as it does with the types of processing used by different companies. The Gawiths and McC (the companies with the best lines of VA, I think) process their stuff in very different ways, bringing out different flavors and characteristics. I'm sure the base leaf differs some, as well, I just don't know that I think it is a question of better or worse base product.
I am curious as what that "something special" will be. The last time I think he used a phrase like that was with Maltese Falcon, leading lots of people to conclude it was topped with something when it was in fact just a different oriental leaf. Of course, Greg has thrown us some interesting topped blends in the past, so there is no telling.
I had almost gotten to the point where I thought he had done everything he could possibly do, and then he came out with Gaslight, which instantly displaced most of my Latakia rotation. I'm curious to see what he's come up with now.