When I first moved to London, I used to commute in every day from Stanmore which is at the Northern end of the Jubilee Line. My Father would go all the way to the other end (Charing Cross) while I would get off at the penultimate stop, Green Park. The service was good.
Please note: The Jubilee Line does not go to Charing Cross anymore (unless you are Jason Bourne). The line has now been extended on from Green Park to Stratford via Canary Wharf (and lots of other interesting places).
I should point out that I am talking ancient history here. The Docklands Light Railway had not yet opened, London City Airport had not opened and not a brick or girder had been laid at Canary Wharf.
Now, I quite regularly have to go to Canary Wharf. If I am going from home, I will pick up the Jubilee Line from Baker Street. Quite frankly traveling from the West End to Canary Wharf sucks.
This morning I was at Baker Street by 7.25am and the Jubilee Line was packed. I've done the same journey loads of times this year and it is always heaving. Yuck.
The problem is, there are just too many people using the Jubilee Line at peak hours. It isn't going to get any better, because they keep on putting new buildings up in Docklands. More buildings = more commuters.
I don't know what the answer is, but it must get worse before it gets better.