The MOST CONSISTENT way to force carb is:
1) Hit the keg with 30PSI CO2 just long enough to seat the o-rings. I hit mine with the 30PSI, then spray the top with starsan and look for air bubbles. If there are bubbles, indicating a slow leak, I purge the CO2, reseat the top, then try again. If there are no leaks, the seating procedure is done.
2) Once there are no leaks, turn the CO2 flow off and purge the keg, which purges both the 30PSI of pressure AND any remaining oxygen. Then put the keg on serving pressure (12-15 PSI for most ales), turn the CO2 flow back on, one more quick purge of the keg to equalize the pressure, and wait about 2 weeks for perfectly carbonated beer.
That's it! All of those extra procedures to speed up this process lead to inconsistent results unless you are extremely precise in the timing. This procedure is by far the easiest way to get perfectly carbed beer.