Isn't IFR flying in controlled airspace just about filing a sensible route at a sensible level, picking up a clearance then either fly the route as filed if cleared or following headings and altitudes as assigned by ATC. In uncontrolled / class G you plan a sensible route and altitude/level and try and get whatever radar service you can along the route.
Its not really rocket science! I think the art is more pre-flight / groundbased in making the right go/no go descision based on forecasts, alternates and available outs with sensible fuel reserves for the conditions!