Something that always bothered me is how poorly Gorion planned and executed our escape from Candlekeep. Gorion is a wise and capable wizard and seasoned adventurer. A mage, especially of his power, with literal years to prepare for this eventually should have had all kinds of plans ready. He has access to fourth level spells, farsight, wizard eye, dimension door, haste, non-detection. It should have been no problem for two people to escape. Invisibility and non detection would allow us to escape undetected and reach his friends that include some of the strongest mages in the realms Elminster Aumar, and the the Blackstaff, Khelben Arunsun.
So why didn't he do any of that... And assuming that we managed to escape... What was his plan? He guides us to meet Khalid and Jaheira... some first level adventurers... Why not points us to his friend Elminster, the chosen of Mystra. He is right THERE... We meet him the following day... He could stop Sarevok by merely wishing it... And even when we meet Elminster he prefers to hide his true nature and all he does is give us pointers and general words of wisdom. WHY?!?
DISCLAIMER: The real reason is that without these events and without his death there would be no game, while others were just plotholes. But let's just entertain the possibility that this wasn't the case. What could be the reason then. All that follows is not canon and simply speculation/fanfiction.
GORION'S DARK SECRET
The truth is... Gorion knew he was going to die...and he follows his fate willingly. His last words clearly foreshadow his imminent death. He was instructed to do so by no other than... Elminster!
Elminster wants to intervene and prevent the return of Bhaal. However he cannot intervene directly. Here is why:
1) This is all bhaalspawn business. Even gods were not allowed to interfere. In ToB the mad god Cyric himself says so, and only has an opportunity to attack you to 'test' you. Otherwise he would like nothing more than to crush the dangerous usurpers to his throne like the Charname, but he fears retribution from other gods. Elminster himself can not touch Sarevok directly for the same reason. It is Bhaalspawn business and powers want it to play it out by itself. Elminster being the chosen of Mystra must have clear instruction to stay out of it.
2) Elminster is also enemies of the Zhentarim, Red Wizards of Thay, and probably more than a few other spellcasters, so interfering too much here could put you in more harms way than not doing so. His involvement would draw unnecessary attention to you.
Even if Elminster could intervene, no-one really knows what the prophecy means or what would lead to the return of Bhaal or how it can be prevented. Since damage prevention is out of the picture, Elminster initiates damage control. If we cannot prevent Bhaal's return, or a Bhaalspawn raising to the throne of Bhaal... Maybe we can have our own bhaalspawn champion. A person that will rise to the top but be able to resist the taint. He has observed Charname in the past. But he is not quite sure yet what type of person he is. He knows Gorion raised you and he has trust in him as a mentor but he knows about your heritage and he is not sure how you are going to turn out to be. Only though the crucible of adventure and with free choice the Charname will show his true identity and hopefully will be forged into the champion he needs. And for that to happen, the Charname needs the right motivation.
Knowing Sarevok is near, Elminster instructs Gorion to leave Candlekeep, to lead us into the ambush where Gorion will fake his death while ensuring that we witness it and then dissappear from our lives forever.
Gorion is reluctant but he knows of our legacy, he knows of the prophecies and he knows he cannot shelter us forever. Gorion likely realized too late that he has done us a disservice by sheltering us for so long. Our destiny will catch up to us and we have to be strong in order to face it. We have to become leaders and not hide behind our strong friends hoping for them to solve our problems. Gorion "sacrificing" himself was the necessary motivation to get Charname to step up and succeed, but of course he had to make it look entirely like an ambush and not that he walked brazenly into that fight.
However Gorion truly caring for Charname did all in his power to assist us in our journey. He pointed us towards his trusted friends Khalid and Jaheira, strong enough to help us but not overshadow us. He let slip information about our whereabouts to Imoen, knowing that she would come to find us...and of course he hid wands, rings of wizardry and ankheg plates from his adventuring days, knowing well enough that we would find them.