I actually did this on the second thermostat before installing it. An old-timey mechanic once told me that trick, drill a 1/16" hole toward the outside of the thermostat on cars that are troublesome to bleed. Seems to have made no difference.Nope. A stuck-shut thermostat will give plenty of heat but the car will overheat since it has no access to the radiator. There are two cooling loops, one for each side of the 'stat, and the heater core gets the bypass loop from the closed thermostat.
OP should drill a tiny hole (1/16") in the top of the thermostat flange. This will give another avenue for air bubbles to escape through, and potentially allow better coolant flow behind the thermostat pebble to better signal it with temperature.