But think of it like rolling a 10-sided dice, where 2 certain numbers will give you a good result, the more you roll, the higher the probability you come across one of the two numbers you want.
But in the case of RE you aren't rolling multiple dice only 1 die. The more you roll it the more likely you are to get the desired number you want, but you still have the same probability of rolling a 10 as a 1.
Ok so for anyone who is still trying to figure this out and having problems understanding it I will relate some of my own experience with RNG in my Video Game Design studies.
My first C++ project was a text based RPG with a combat system. To make the combat system not be a Hulk Smash style thing. I had to come up with a Random function to randomize the damage while still making it possible to win and lose. I decided to make it possible to crit and miss based on the # generated with the random roll. I tried going the easy route and using the standard time based single Random function, that failed as you would get streaks of hits and misses that wouldn't end until time shifted enough to make a difference.
I attempted to change it by making nested Randoms with the result of the first being the basis for the subsequent result. Same result.
So I decided to introduce a pause into the function. At that point it actually worked, while it wasn't truly random, it did have enough variation within the outcomes to appear random. It worked because I forced a time shift into the code, same thing Bioware does by making us cast the RE. Granted it is a false random because the only thing that would actually be able to change the outcome of a Random function call is time, but by forcing a time change by making us cast the RE attempt. they allow for a series of nested Random #s to be generated, with the # generated affecting subsequent results until the cast is finished and a final # is selected. Your complaint that it isn't random is true, but to say that the tool tip is incorrect, is flawed, & unless you can get access to the code and find the specific string of code which relates to the RE results it is actually slanderous. Be glad that Bioware is letting you vent your frustrations here. If you took this to a public forum and made any money off of a website, or news article with that in it they could actually sue you.