Why do creationists always insist on changing the meanings of words? Why can't you just use them to mean what everyone else does? RWP is right, a scientific conjecture is far weaker than a scientific theory.
Just because one word is stronger than another does not mean it carries an entirely different meaning. It is not that creationists wish to change the meaning of the word "theory," only that they wish to remind science of its limitations. Get used to it and get over yourself. You are dealing with a universe upon which you and all science is continually thrusting conjecture. There is neither harm nor shame in that.
Do you believe the earth travels around the sun because you've observed it with your own senses, or do you believe it because someone told you so? Doubltess there are a handful of people who have been given to observe it with their own senses. When they report to the rest of us, they are preaching a truth to hearers who must weight for themselves whether what they are hearing is true or not.
Based on the heliocentric theory's effect on mankind at the time it was preached, I'd say human reason is gullible, and fully capable of deceiving itself. I don't believe human reason has evolved much in 400 years, only that the amount of information available for consideration has grown immensely.
If one desires evidence that human reason is sorely lacking in judgement to this day, one need only observe the fact that William Jefferson Clinton served as President of the United States for two terms.