@cug: Thank you for taking the time to answer my questioin.
It seems that taking pictures of moving objects can lead to different results. This video from May 2014 shows a comparison of four mirror less cameras and a Nikon D4s.
At that pre FW 4.0 time the Fuji T1 was the slowest, but still capable. They also came to the conclusion that the Panasonic GH4 also mirrorless comes very close to the Nikon D4s.
My point is not to discuss if a morrorles has 90% or 99% of the performance of the D4s. But even 80% of the best of the best DSLR should be usable in many cases. Your experience obviously is different where you came to the conclusion that the T1 can be used for stills and slowly moving objects only.
So apart from all objective measurements the subjective user experience can be very different.
As the above is just 2nd hand information here my own experience:
At good light condition the auto focus is quite fast but it becomes slow and inaccurate if the light becomes dim. My biggest problem when trying to track a moving object is the long time where the viewer is dark after each shot.
I'm having a hard time figuring out why they chose to test the X-T1 with the 55-200 instead of the comparable 50-140. It is the lens that is the highest quality and the most comparable to the other lenses tested on the other bodies. Do any of you feel that the 50-140 would have allowed the X-T1 score higher?
Edit: Nevermind. The information I'm finding is that the 50-140 was introduced in November of '14 and this video was published in May '14. That explains why they didn't use it, but in my opinion, it also drastically changes the outcome for Fuji with all the firmware upgrades since then...