Having a lot of LOBs and RISP is a good sign for a team, whether they are able to get those runs in or not. "Clutch hitting", unfortunately, is not a sustainable skill.
"Cluster luck", clustering a bunch of hits together to score a lot of runs is just that - luck. It is also not a sustainable skill. Nor is it a sustainable skill for a pitcher to be able to scatter hits.
I'm not saying that getting hits for a batter or avoiding hits for a pitcher is not a skill. I'm saying that the clustering of such hits is not a skill.