Two miles is a lot...
Most airways are eight nautical miles (14 kilometers) wide, and the airway flight levels keep aircraft separated by at least 500 vertical feet from aircraft on the flight level above and below when operating under VFR.
Military Training Routes are divided into Instrument Routes (IR), and Visual Routes (VR). Each route is identified by either of these two letters, followed by either four digits for routes below 1,500 feet above ground level, or three digits for routes extending for at least one leg above 1,500 ft AGL. (i.e., VR-1056). The difference between the IR and VR routes is that IR routes are flown under Air Traffic Control, while VR routes are not.
Airspace above the United States from the surface to 10,000 feet above sea level is limited to 250 knots (indicated airspeed) per the FAA's Federal Aviation Regulations. This speed limit hinders most modern-day tactical aircraft training operations, since low-level strikes are conducted almost exclusively at speeds exceeding 300 knots. Military Training Routes are usually limited to 420 knots, and in no case are aircraft allowed to exceed Mach 1 within United States sovereign airspace, except in designated Military Operation Areas. While on the route military aircraft squawk a Mode C Transponder code of '4000', which informs controllers that they are 'speeding' on a route. This squawk however is only legal by military aircraft, while inside a properly scheduled route corridor. MTRs do not constitute an official airspace, and are all open to VFR or IFR civilian traffic; however only military aircraft are allowed to squawk 4000 and exceed 250 knots.
Each route is defined by a number of geographical coordinates and their respective navaid fixes. From this line the corridor is extended a specific number of miles, in the vast majority of cases this is five miles, making the corridor 10 miles wide. The Routes are individually operated through one of the local military air bases, which schedule and 'own' the route. The FAA requires these bases to 'NOTAM' out the routes at least two hours prior to use to allow for civilian traffic to de-conflict if needed.....