Super User
TOCSV ( Summary, -1 ) behaves as I expect with no ID filtering and with ID IN {1,2,3,4}.
TOCSV ( Coeffs, -1 ) behaves as I expect with no ID filtering but returns empty tables with ID IN {1,2,3,4}, except for the Total row.
If I filter out ID = 5 in the query editor before loading the model (rather than via a slicer), then there's no problem.
I spent several hours trying to debug this before I posted, both in Power BI Desktop and using the debug feature in Tabular Editor 3 and your suggestion was one of the first things I tried. I didn't just run into a problem and post an issue without doing any of my own research. Instead, I created a simple example demonstrating the strange behavior so that others can quickly and easily reproduce it.
I'm certainly open to debugging suggestions but I'm getting the sense that you didn't open the pbix I included with the original post. There's clearly something weird going on here as Greg_Deckler has confirmed. All other replies so far seem to assume I'm clueless.