My last performance before Christmas was the Messiah with Chorus Angelorum and members of the Bath Philharmonia in Ottery St Mary. I worked out that I must have sung at least nine performances of this now (here’s an account of the previous one), and probably most of them from the same vocal score, so I really should go round systematically rubbing out markings (apart from notes to myself about such matters as particular notes which are hard to tune and so on).
This particular performance had few cuts (of the choruses, only Let all the angels of God and But thanks be to God were lost).
Our conductor gave us useful advice about tackling the runs, which I will pass on. Try consciously slowing them down (obviously while keeping in time with the conductor). I was a bit sceptical about how one could do this, but it really worked for me.