The only time I ever pre-filled an oil filter was when it was installed vertically like the SB 350 Chevy.  If it's at an angle, don't bother.

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If possible I like to do it.

If it's at an angle I only add enough oil to where the element is soaked & it won't spill.

As @doc mentioned vertical is when you really fill it up. The Ford modular engines (atleast on SuperDutys) have that but oddly enough the same year F150 with the same engine will have a remote mount horizontal filter behind the front bumper.

In the case of the latter I only filled it half way then spun it on before it could leak.

An argument against doing pre-filling oil filters is the possibility of introducing dirt or grit in with the oil due to a dirty funnel or other means. Any such debris would be pulled right into the engine without being filtered out.

Yes it's recommended and better for the car so there will be some oil flowing for pre lube so you don't dry start the car.

Unless it's a 1qt diesel filter, I wouldn't bother if it's not recommended in the service manual.. Those little guys fill up so quickly.

I've not noticed any difference. Have done oil changes both ways and would only do it if the filter was more or less vertical. Don't believe it matters either way.