Hoi Alessio, as far as I understood it and remember, this is nearly like the first solution discussed on Monday. But then we (at least the people at SLAC) felt that maybe this adds a bit of inflexibility (since the ntuples need to be redone in case the TS lists are screwed), so we were discussing whether and how to implement it on the anaRecoil level. I don't see any reasons why not to do what you propose, as long as the number of iterations on the TS lists is small. I.e. can we completely validate the TS lists before making the new ntuples? In fact, I'd prefer the move to ibu because anaRecoil is getting slower over time as new features are added, and this TS comparison would not help. Cheers, --U.