First, I think that you are taking alot what you quoted from the Flightglobal.com article out of context. Here is the original ariticle for those interested. P&W signs off successful GTF flight-evaluation effort. The article is discussing the possibility of a larger evolution of the GTF later down the road that might be fitted to larger aircraft than the CSeries. It doesn't imply in any way that the GTF is unoptimized for the CSeries. While the CSeries concept has existed in some form for many years, the most recent design is a recent development that has been reincarnated from older, now dead CSeries projects. The newest CSeries that is set to see production in the future has been designed from the start around the original P&W GTF, not a scaled-down, less efficient "mini" GTF. I'm sure that Bombardier will take the fan diameter into consideration while designing the CSeries' landing gear. Applications of the GTF on smaller jets such as Embraer's E-jets are unlikely though, because either a smaller, less efficient GTF would need to be hung, or the E-jet's gear would need to be extended, in addition to a strengthened wing. I think this might be what the article alludes to.

Also, P&W probably assumes, like many people in the industry, that neither Airbus nor Boeing are in a position to develop a new narrowbody right now. Boeing has their hands full with the 787, while Airbus is still drained from the A380, and currently placing most of its remaining resources into the A350. Their financial resources are mostly drained, and the airlines aren't doing much better. Why would they announce the development of a new narrowbody, their largest source of orders, when they currently have a large backlog of orders for their current narrowbody offerings? These provide a reliable source of income, and the announcement of anything new might influence their customers to convert existing orders into orders for a new aircraft that wouldn't be delivered until possibly 2015 at earliest.

I agree though, the CSeries is a huge risk for Bombardier, not only in their choice of using unproven composite technology, but also because their orders for their existing lineup of aircraft are diminishing. For the company to survive, it must create something new, and it realized a market niche between current large regional jets and mainline narrowbodies.

I, like almost all of you, hope that they will be flown by the majors, but really don't see this being anything to worry about. I'm really not too familiar with scope clauses, but it seems unlikely that any major would allow these to be flown by a regional. Correct me if I'm wrong, but it seems that things would need to change drastically for that to occur, and I don't think this will simply happen because this aircraft will be manufactured by Bombardier. This is Bombardier's breakthrough into the majors, and not just another regional jet. I'm just welcoming an exciting new clean-sheet aircraft design, and hoping the best for it.