Currently we expect users to only define a oned cross from the start, and retrieve whatever quantity they want with the phase/real/imag/mod methods. This is fine but we also would want to be able to get frequency dependent methods from a two-d cross. This also happens currently but it always goes through _oned_cross. Instead we should only go through that method if we are defining a new reference band; otherwise, going through the existing cross product makes more sense and is faster.
Currently we expect users to only define a oned cross from the start, and retrieve whatever quantity they want with the phase/real/imag/mod methods. This is fine but we also would want to be able to get frequency dependent methods from a two-d cross. This also happens currently but it always goes through _oned_cross. Instead we should only go through that method if we are defining a new reference band; otherwise, going through the existing cross product makes more sense and is faster.