Re: In a simplistic view of things, Merom is kind of a hyperthreaded version of Yonah, implemented in the DFM in a similar way.
I see what you're saying, but I think you're WAY off in this case. Intel presented Merom at IDF as an actual 4-wide issue processor micro-architecture. They would not have emphasised this in their summary slides if it were just a DFM feature.