The current two-hour margin for block time discrepancies is highlighted as excessively lenient, allowing for a significant degree of inaccuracy in setting computer clocks. However, the proposal of a stricter +/- 10 second rule raises concerns about its feasibility and the risk of exacerbating issues related to block propagation delays across the network. These delays, while typically spanning only a few seconds, can occasionally extend to approximately half a minute, underscoring the variability and unpredictability inherent in the system.

Further analysis is provided on the method for estimating propagation delays using an exponential cumulative distribution function (CDF), drawing from data presented in a cited paper. This approach, based on the orphan rate observed from ForkMonitor's feed, offers a mathematical framework for approximating delays, which is crucial for understanding and potentially mitigating the impact of selfish mining practices. Selfish mining, particularly by entities controlling more than 33% of the network's hashing power, is identified as a significant concern due to its ability to artificially inflate the orphan rate and thereby distort estimates of propagation delay.

The concept of implementing a rule that prioritizes blocks based on their arrival time to the timestamp is discussed as a countermeasure against tip races caused by attackers. This strategy entails miners selecting the block whose arrival time is closest to its timestamp and shifting allegiance if it becomes evident that the majority hash rate has coalesced around a different block. The debate extends to the treatment of blocks found beyond the Fastest Transmission Limit (FTL), pondering whether such blocks should be temporarily excluded from consideration by miners, thus creating a so-called penalty box to deter certain types of attacks.

In summary, the dialogue underscores the complex interplay between network security measures, the accuracy of timekeeping mechanisms, and the strategies employed by miners and attackers within the blockchain ecosystem. It highlights the need for a careful balance between stringent rules to prevent manipulation and the flexibility required to accommodate the inherent uncertainties of block propagation times.