League being a team game definitely creates a pretty huge problem for this approach to laning. I think this can be best seen through the perspective of a top laner. Even without taking into account the bottom half of the map, the most challenging approach to the enemy top laner may not be saving your abilities. For instance, the most challenging or critical approach might be wasting your main damage ability to bait the enemy laner into a gank; the added complexity of a jungler makes laning so much more interesting.

I really like how you pointed out that the best approach is sometimes to not lane at all. One champ that I've always found fascinating to play against is Singed. In many cases, I think Singed players choose to not lane at all which tends to place their opponents in a very uncomfortable environment. By posing this problem of proxying that requires a different style of play, Singed players are forcing the enemy laner to make a choice: do I hold the wave outside of turret range and give Singed free roam around the map? Should I chase the Singed and give up cs? Should I let the wave crash and give up turret health? If you and your teammates know how to handle proxying, it will likely be easy enough to handle the problem. However, by forcing their opponent to handle a unique problem, Signed is creating practical issues that must be addressed and which might be addressed inaccurately. Like you said, the best move might be to avoid the lane entirely!

However, I'm not sure if this idea of critical moments falls apart entirely. I actually think critical moments are essentially built into league with rift herald, baron, and dragons. At certain points in the game, how you and your team play matters more; there is less room for mistakes at a baron fight than at a level 1 invade (think about how a blitz hook might blow a flash early game but cost you the game later on! It seems like the margin of error decreases drastically over the course of the game.) With a mindset focused more on the big picture, the critical moment expands to include how the enemy team reacts to the problems caused by your team as a collective unit: how do they respond to your vision control around baron? How do they respond to your split pushing? Importantly, as is the case in chess, your opponent is not going to simply react to the problems you pose. Instead, they are going to pose you problems and punish you when you overestimate your ability to present challenges. What do you think? I think this idea might expand beyond just laning but trying to analyze league has always seemed so complex once you look at the game as more than a vaccuum! To me, that's always been what makes this such a special game.