Lars Hellström <[log in to unmask]> writes:

> What I suspect is the right solution is to have \protect set to
> \@unexpandable@protect when scanning for \omit and have it reset to
> \@typeset@protect in the column templat
> ... I doubt this can be
> done by patching the \halign primitive, but it could be built into e.g. the
> array package.

I agree.