What they are doing is just nonsense. You can use the four normal constants: gravitational, speed of light, plancks constant, boltzman constant, or the Planck ones, also four (time, mass, length, temperature). What they do is just rewrite the G, c and h-bar, the only ones that appear here, in their equations and it turns out just only two appear in the equations. Which two? Planck length and "energy", where planck energy is a combination of time and mass... so it is still three! All this nonsense to try to say something of no particular interest: if you look at a very small subset of expressions you can probably redefine some constants conviniently to get rid of others.