The problem is at the particle (coffee grind) level, some are positively charged, others are negatively charged. The result is that if two particles of the same charge come close together, both will shoot out in opposite direction, and that direction is not necessarily where your basket is, and it will make a mess. If however, two particles of opposite charge come close together, they will stick together and neutralize, but by doing so, they will form a clump that may cause uneven extraction.
The idea with spraying the beans with water is to prevent static buildup before particles have a chance to form clumps or make a mess.
To your second point, one of the fascinating things about this study is that the static charge during the grinding process causes the coffee to clump - that means that by the time the water hits the coffee puck it is too late to avoid the static-induced clumping.