Yes, it did a job for BBC2 especially but I wouldn't say it was the breakout hit in the way Deal or No Deal, Pointless and The Chase were.
I have to disagree with you there and say that the Weakest Link has/had been a massive breakout hit for the BBC.
The format been sold to over 75 different countries, yes in some it only lasted 1 year/series etc but in several countries TWL lasted for many many years, France for example. The British original plays out (even to this day) all over the world, 20 years on.
Compare Weakest Link to Pointless (which you claim is a breakout hit?)
Weakest Link started in August 2000 daytime, no real hype or promotion, same as Pointless in August 2009 daytime.
Weakest Link massive hit within weeks, sold like mad in 2001/2002 around the world. Pointless format not really selling like hotcakes like the weakest link was. Pointless apparently has sold to 12 countries outside the UK, with only 3 still airing/making it.
Weakest link like I say sold to well over 75 countries, with to this day still being made/airing in 5 countries.
Weakest link original BBC run was for 11 years, 7 months. Pointless currently at 11 years, 1 month. Both series well over 1000 eps.
Pointless feels like it's on the downwards slope towards its twilight years now ...and let's face it, as soon as both hosts decided to call it a day, the BBC will end it....just like Weakest Link when Anne had enough.
And with the Weakest Link looking like it's about to make/have a new comeback spurt (The U.S. and possibly here) I would say it's the strongest format the Beeb have compared to Pointless.