I don't think your analogy is good. The troubles of actually doing the operations but no trouble of what's happening at the artistic level is coming from your m

I don't think your analogy is good. The troubles of actually doing the operations but no trouble of what's happening at the artistic level is coming from your missing a few key steps at level of nuts and bolts... it is more similar to how you can picture in your head a beautiful dog... But when you try to convert that image in your head to pencil you get stuck... Knowing some artistic techniques may help (perspectives, shading) Practicing mathematics exercises would be like practicing your technique ... It takes some time to develop the expertise. Then when it's time to do math you can use your techniques so avoid letting small details trip you up and let you focus on the bigger picture.