Should a history of losses and training losses be explicity returned?

[ablaom]

Currently the workflow is to define an external variable and use the "callback" control WithLossDo - but perhaps there's an argument for collecting a history of the loss (and training loss and iteration count?) and returning these.

See also this discussion.

[ablaom]

I think a better (more general) idea is to add a wrapper that replaces the returned report for a control with a complete history of state for that control.