Everything I'd want to say has already been said but I'm really curious: just why would you think we are "risking all of eternity believing?" After all, TEs are still Christians ... right?
I agree with your curiousity and that TEs are Christians. But I disagree greatly with much of what was said in response above your post.
Perhaps you can argue that the OP implies the view that TEs are not Christians. That would pushing the OP language pretty hard. Helen can speak for herself on that. "Risk" is not the same as "lose".
IF one where to simply take the Word as fungible with other "wisdom", then, yes, there is a problem. If one is to be guided by one's own good sense, which the WOrd only happens to fit as a fortunate coincidence. Yes, there is a problem.
Pro 3:5 Trust in the LORD with all thine heart; and lean not unto thine own understanding.
To that extent, Helen's OP clearly extends to us in one way or another. Not taking the Word seriously has consequences. Some of those mistakes, I still make. THinking for yourself, without God, is indeed like any other venture done in your own strength. It is hazardous.
Mat 4:4 But he answered and said, It is written, Man shall not live by bread alone, but by every word that proceedeth out of the mouth of God.
Some folks here (TE and otherwise) come to the matters in Genesis with a devotion to the Word, desiring to be grounded in it. Yet, elsewhere in this forum, there is a cavalier attitude to whether the Word is true or not. Paul also says work out your salvation in fear and trembling. If you just give yourself a pass on sorting out a conflict with the Word simply because you are a modern person and the prophets were not, that is pretty unscriptural. You can call that a difference of philosophy, but I don't think that means those of us who believe inerrancy should ignore what we see as a problem. That we may get in someone's kitchen on this issue from time to time doesn't make us wrong.
If the Word doesn't fit what we observe, there is a remedy. But, it is not confidence in our observation. Devotion actively seeks an answer:
Jam 1:5 If any of you lack wisdom, let him ask of God, that giveth to all [men] liberally, and upbraideth not; and it shall be given him.
As for how the Word was designed, I wholeheartedly agree that the Word was designed to be understood in its affirmative statements. That is probably a good study for us that should not be so simply dismissed as above.
I also believe the WOrd was designed to make salvation as simple as possible from a empistemological standpoint and that it had do it this way:
Rom 10:9 That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved.
I am not sure that confession is all that important to some folks here. I know for a number of TEs it is vitally important. I would say that as Christians they have security.
But, as James teaches, doing right shows that your heart is with God. Dismissing the Word as a mere part of the buffet of ideas is not the heart God wants and is hazardous.
As for words such as "preposterous", I am not sure where that is coming from. But if the following is also preposterous, then I will have a better idea of how we differ:
Rev 22:18 ¶ For I testify unto every man that heareth the words of the prophecy of this book, If any man shall add unto these things, God shall add unto him the plagues that are written in this book:
Rev 22:19 And if any man shall take away from the words of the book of this prophecy, God shall take away his part out of the book of life, and out of the holy city, and [from] the things which are written in this book.
This would seem to apply to that particular book, I guess. However, if some there think this language might be hyperbole or paranoia, I think that is what Helen is talking about in part, though it is not TE "origins theology."