It's about following the construction of a coaster, not speculation. Speculation is making a prediction off of no evidence. Just becuase the ride has the trains on and is together doesn't mean that it's certain that testing will happen on Monday. In the end, it can confuse people.
spec·u·la·tion
noun
1. the contemplation or consideration of some subject.
2. a single instance or process of consideration.
3. a conclusion or opinion reached by such contemplation: These speculations are impossible to verify.
4. conjectural consideration of a matter; conjecture or surmise: a report based on speculation rather than facts.
5. engagement in business transactions involving considerable risk but offering the chance of large gains, especially trading in commodities, stocks, etc., in the hope of profit from changes in the market price.
^that's the definition straight out of the dictionary
and another:
speculate
— vb
1. to conjecture without knowing the complete facts
not "nothing at all", just not the complete facts