[Tscarborough]

If it is fresh (day or two), I would use an acid solution and a stainless steel wire brush. Work the edges and the joints will narrow down. It looks like he tooled the joints while they were still too wet.

 

[Tscarborough]

Stacker, the "mason" tooled the joints while wet and smeared the tuckpointing mortar all over the edges. Grinding them out will not remove that. Maybe the soda blasting will work; I have no knowledge of that technique. Using a rubbing stone will also work to a certain extent, but it is hard ass labor. Done very carefully, an acid will remove the smears, but it is more likely that the brick will be burned in the process.

What this illustrates is that there should ALWAYS be a sample area/panel done, both to show competence, and to give a measurable standard by which the completed work can be judged.