Caching preview

Is it possible to get a preview in the viewport whilst you cache? I cache a lot and find it would be useful.

If by preview you mean for the viewport to update as you cache, then yes, this should be the default behaviour.

There is an option to freeze the viewport while you cache, which can be 50% faster or more, called Fast and Loose. Could you have accidentally ticked this setting?

I realised you said “cache” and not “record”, are you referring to the Edit → Cache button?

If so, then yes setting the Cache attribute on the solver to Static and hitting play is the exact same thing that happens when you click that menu item, and would give viewport updates as it happens.