I agree that assumptions are bad for science. RE science is built on centuries of assumptions. FE science is based squarely on the zetetic method, which does away with assumption and bases the conclusion entirely on the result. That's how Rowbotham proved the Earth flat a century and a half ago, and many FE scientists have since duplicated with the same result. I suggest you do some research.
And it's not the government per se that's behind the Conspiracy, it's NASA, in concert with the world's various space agencies. They are far more intelligent and cunning.
lol
Scientific method is your friend.
With any experiment you must have some kind of assumption (hypothesis) our you wouldn't have a clue as to why your doing the experiment in the first place 
No. Your approach is to say "I propose that the Earth is round" and proceed with that hypothesis in mind, leading to hopelessly biased results. The far more sensible approach, the zetetic approach, is to remove the hypothesis altogether, ask "What shape is the Earth?" and proceed to collect evidence, basing the result entirely on the evidence rather than having some hypothesis in mind. This removes the bias. That's how Rowbotham originally did it.
My approach is to say hmm gravity. What tests can i conduct to ascertain what this is?
Well I assume apples and feathers fall. Lets drop them.
Result: What? they fall at the same rate. But one is heavier than the other.
Hypothesis, Theory
Next assumption. Oh look loads of stars in the sky. What are they?
Well they seem to move around the sky in an arc like fashion and at a certain rate. Why do they do this?
Lets measure the rate at which they move and what the angle of there moving curvature might be. Hmm what kind of experiment shall i conduct. Well lets assume the stars stay in the sky and move in a manner I can track with a telescope.
Result: Oh look the stars move around in a weird fashion that could mean the earths round.
Don't get me wrong I agree with what you are saying. But even Rowbotham had to assume that his appratus worked in a certain way to give him results that he could analyse.
Experiments stand on other experiments. Theories stand on other theories. It's how science works. If a theory at the bottom fails then the rest come tumbelling down.
If Columbus didn't use a previous hypothesis of the world and where land masses that have already been discovered might be he might not of found America or he would of found it not as soon as he did.
You need to stand on giants (so to speak) to get that much higher.
Experimental apparatus are built on previous theories that say it will work. i.e. and electron microscope or a SQUID (Supercoducting Quantum Unified Interference Device) which has a joesphson junction at it's heart.