Bill Tindall, E.Tn.
I have only used the commercial product....primarily Mohawk. It goes on silky smooth, stays the consistency of heavy cream for more than enough time to refine the appearance by wiping and brush. It is the easiest part of the finishing schedule to deal with. Such a thin layer is left behind there will never be an adhesion of cracking problem.
As you sure you were not thinking of filler? That has the issues you describe. It takes some experience.