It pays to just think: why are S and T (in different ways) related to the concept of fact? Because S processes the idea of actuality, and T processes the idea of explicit. Facts are built on these two things. This is why Jung would have viewed the ST type as the prototypical scientist.
The difference is best understood like this: the properties of ice cream you can express logically are T. But there is a part of your direct sensual interaction of it that you cannot abstract away into logical form. That interaction is what is the strong intuition that has you declare it to be real.
The reason Te is associated with progress is that if you can't explicitly measure it even in principle, there's no way of telling if there was progress. Se is more your ability to interface tangibly with the world, and is more instinctual.
I diverge heavily from the mbti take on some of this stuff, because I think the idea of Te being "action-oriented" tends to render unclear the difference with Se. T is in general logic-oriented, and not really action-oriented -- I'd point much more to Se for the action.
The origin of the idea that Te is "action-oriented" is actually a problem area arising both from the association of TJ with Te (Myers' conversion formula) and Jung's association of extraversion with sensation (which he never fully distinguished from his sensation function). The idea was simple: he wanted to say an orientation to the outer world => a concern with sensory objects, the concrete, and a less reflective temperament.
Trouble is that he was basically going against "materialism," prevalent in the sciences, and his analogy breaks down: most of those he was describing were far from unreflective, and merely much more concerned with making things explicit/precise than Jung was, as they didn't want to become mystics. More problematically, if one reads jung's introverted sensation type portrait, he literally contradicts the idea that sensation involves an orientation to reality, which he holds to in other places. So really, it's a mess, and arises from his wanting to have it both ways: be a scientist, yet be what he called an "introvert" -- someone oriented to the inner life, which is traditionally associated with religious>scientific tendencies.
Besides this, his ideas are pretty great, and I just revise where it's unmistakably necessary.
