For the most part my sentiments are a reflection of all the rest on here, but I have a few points and a question based on your statement there:
Are you sure she was an INTJ?
What you've described could easily be either an INTP, as bethdeth was suggesting (I think, she didn't really specify), or an INFJ. Despite the F, INFJs can come across as incredibly intelligent, my boss is an INFJ and your description would fit her rather well. She does very well at running the logistical side of the business, and is often
seen as a very logical person, but is very quick to jump to conclusions based on little information. Most frustrating is her near religious fervor once she has made a decision unless you can present her with ten-times the information she made her original judgment on showing that she was incorrect.
An INTJ may not remember the details later, but at the time a decision/conclusion was actually made the mind was consumed with every relevant piece of information and all possible ramifications of that decision. I may not focus on it, or make it known generally, but in such instances how other people are affected is also a key component of my decision making process. Details are also kept on a subconscious level, so even though I may not be able to consciously recall, the information is still there. It's amazing the level of information that can come seemingly out of thin air when I actually need it.
The INTJ mind is more akin to a Thesaurus than a Dictionary. I may not have all the facts at hand to describe things properly (thus irritating the S types to no end) but my level of associative reasoning is equally unfathomable. Its a memory paradox, if all those details stayed near the surface, our intuition wouldn't have room to operate.
Because of the subconscious nature of those details, making a decision or coming to a conclusion is like mixing fluids of similar density, there can be fifteen or twenty bits of information and all of them will coalesce at the same time, those which don't fit properly, or have an incorrect density, are immediately discarded, while the rest form a cohesive conclusion, all in a single brainspan. Once that idea has formed the individual fluids/details are no longer necessary and return to the subconscious.
Changing an INTJs mind is actually easier than it seems, as our minds are rarely ever truly made up. If I have made my decision on six details, you need only show me seven details in contradiction and I will immediately reform my opinion, that may only go so far as for me to find two more details reinforcing my original assessment, but I will reform my opinion if the scales are tipped even lightly in your favor.
The difficulty with that is: I rarely form any kind of serious opinion/decision on less than a significant amount of information. More so than anyone near me at the time may realize.
I'm just wondering. I had an INTJ boss who was often terrible at picking up on details, and I think that this caused her to jump to conclusions a lot, unless someone gave her indisputable facts. It irritated me that she was so unobservant. I know she was pretty smart and could be detail-oriented because she made excellent grades at school and got into a good grad school program, but I don't think she picked up on details that didn't affect her very much. I didn't like how she made judgments without getting the facts straight.