I figured the use of the word "potentially" (twice in that ann)...

I figured the use of the word "potentially" (twice in that ann) meant "this is what we think based on analysis and what we currently know".. where reality will prove them right or wrong once they've tested PL4. I at least took is as a sign of confidence, I'd never expect anyone to be so confident as to say there is zero risk and success is a given. I get your point though, I just think t there must be so many factors/variables/complexities to consider. Probably a case of "the proof is in the pudding" etc, hopefully we'll be put out of our misery one way or another soon enough!