Post
The theoretical fastest time a human could ever achieve: the speed of light for speedrunning, always approached but never quite reached.
The human limit (or 'sum of best segments') represents the theoretical fastest run possible by a human, calculated by combining a runner's best time for each individual segment of a run. In practice, no one achieves their sum of best because it would require hitting a personal record on every single split in a single run, a statistical near-impossibility. The concept creates a fascinating asymptotic curve: as runs approach the human limit, improvements become exponentially smaller and harder to achieve. A game's world record might be 30 seconds from the sum of best, but closing that gap could take years of attempts. TAS times provide a different ceiling, the absolute theoretical limit regardless of human capability.
Example
In Super Mario Bros., the human world record has been within seconds of the TAS time for years. Every improvement now comes from saving individual frames through sub-pixel optimization and frame-perfect inputs. The gap between human and TAS performance has shrunk to the point where some segments are literally TAS-optimal, with remaining improvements measured in individual frames.
Why it matters
The human limit concept gives speedrunning a philosophical depth beyond simple competition. It asks whether there's a 'perfect' human run and whether we'll know when we've hit it. It also frames speedrun records not as absolute achievements but as points on an asymptotic curve, always improvable, but with diminishing returns that make each new record exponentially more impressive than the last.
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