After only 2 rounds of the NRL played the sample size is quite small, however it has given us a glimpse into the ramifications of the newly instilled rule. As opposed to blowing a penalty and slowing the game play, referees are awarding a set restart for majority of infringements.
This is improving the "Ball in Play" metric that the NRL seem vital to improving the game, although there are so many worse time wasting facets (lining up goal kicks) that this seems like a minimal gain overall.
Referees seem more inclined to give away the set restart for minor infringements as they know it doesn't give as much advantage as a typical penalty did. It also limits the choice of teams, negating the early penalty goal that Wayne Bennett-coached teams loved so much.
The issue with the new rule is that it has potential for abuse, with teams like Melbourne inevitable to exploit it as they have been known to do to rules in the past.
With this new set restart rule, a team would be silly not to abuse it on first tackle. You keep the opposition pinned in their end. Their forwards have to travel further to get back on-side. Teams are able to get their defensive line set and essentially get no punishment as it was zero tackle already.
Those first few runs, usually scampers by the back three, are now met with set defensive lines instead of broken play, limiting the potential for highlight reel plays and severely limiting meters gained during the set.
The essence of the rule is to keep the game free flowing and not letting the big guys get a rest, thus trying to bring the little guys back into the fold. But the way I see it unfolding, it's just going to result in a tactical give away making the game played between the 20s and less attacking opportunities, therefore less tries and excitement.