[Roger Cole]

So basically, paper is not orthochromatic (blue sensitive only) it's just not red-sensitive. Or graded paper is blue sensitive only and MG paper is blue and green.

As far as contrast is concerned, graded paper will shoot at its grade, no filters required, MG paper negs will allow me some contrast control if I use my printing filters in front of the taking lens.
If I don't put filters in front of the lens what will it shoot at? Like a 1.5 -2 ?

Nominally grade 2 without a filter, but that will probably look pretty contrasty when shot as a camera original.

You don't necessarily have to use your MG filters. Yellow filters will reduce contrast; magenta filters will increase it. I don't know about you but I don't have any magenta filters in my camera bag but I DO have yellow. I used a #8. Not as precise as adapting your MG filters but it does work.