Comment (by Samuel Cupp):

My previous comment was incorrect, as I forgot to also set update_Tmunu. I do get nans when I set that. I haven’t tried to debug this, but my guess is that moving this to a different bin leads to the A->B routine happening in a different place relative to con2prim, which causes this issue.

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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2497/illinoisgrmhd-is-incompatible-with-setting