I was heading to bed when I just thought of yet another plothole in Fallout 3..
Ok so here it is.. Doctor Madison Li is credited with getting Liberty Prime working again right? Ok so when the Enclave take over Project Purity and we are forced to flee from it and Li takes us to the Citedal.. it is shown that she knows Lions and the Brotherhood very well. She is even allowed to walk up to the intercom can demand that Lyons lets them in..
We learned that the Brotherhood helped James and his people with protecting project purity. It is why Li feels that the BoS would and could protect them. When she is allowed into the Citedal, she is allowed to move around freely and even work on Liberty Prime..
So my question is.. Why didn't she get Prime working decades ago? She was able to fix it in just a couple of days so surely she could have taken a look at it long ago and fixed it then. Which means the BoS would have never have had to stay in DC for as long as they did.
The Brotherhood know that Li, James and the others are super smart people, and they clearly had access to the Citadel before and we know that these Brotherhood aren't complete isolationist tech hoarders..
So why was Dr. Li never asked to look at Prime in all that time? She never walked around the Citadel before and said "hey would you like some help with that giant robot you guys have?"