Why do the tentative words bother you? That's how science works.
Hypotheses are developed. They use words like "may" and "might."
Seriously, do you have a problem with science?
I have a problem with people, whether politicians, salesmen, or scientists, making exaggerated claims and predictions simply because they sound good.
Some scientist have made and are making unrealistic preditions about the speed with which therapies will be produced. Here is an article from last year, "Medical Value of Stem Cells 'Over-Hyped'", in which Robert Wilson, a professor of fertility studes at Imperial Colleg London, cautions "I think it is unlikely that embryonic stem cells are likely to be useful in health care for a long time."
In another article on the same subject, "Stem Cell Hopes Distorted by 'Arrogance and Spin'", it says that scientists are being over-optimistic and providing a "case study in scientific arrogance and the danger of 'spining' a good story."
Hypotheses in science are never proven. What a scientist can do is collect experimental data that supports the hypotheses. Einsteins theory of relativity has never been proven and can't be. Inductive reasoning from experimental is not a proof. All any one can say is that the data supports the hypothesis. Someone may come up with a better hypothesis later on. Indeed, Einstein spent the last 35 years of his life trying to find a unified field theory that would reconcile his theory with quantum mechanics. He failed.
But a predition of the speed with which therapies will be found is not a hypothesis. It is only a prediction, and not a very good one when it is done simply to get research money. What I am asking for is to cut the hype and be more realistic about what may be possible.
Their are huge obstacle to overcome. Scientists do not know the mechanisms to direct embryonic stem cells to specific types of cells. There is also some evidence to suggest that such adult cells could spontaneously revert back to stem cells, or start growing in distorted and unpredictable ways like a cancer.
And what about proper peer review? A Korean scientist faked cloning experiments and lots of people simply accepted the findings because they wanted them to be true. That is not good science by any stretch of the imagination.
Let's all just cool the hype.