The estimation of capacities and traffic performance at two-way-stop-controlled (TWSC) intersections has been the subject of investigations conducted by many researchers. The results of these investigations are incorporated in highway capacity manuals like the U.S. Highway Capacity Manual (HCM) or the German Handbuch für die Bemessung von Strassen (HBS). Although the underlying methodologies are similar, there are two major differences between the current HBS 2015 and HCM6: (a) the procedure for the impedance factor for movements of rank 4 and (b) the procedure for estimating the capacity of shared short lanes for both minor and major movements. In HBS 2015, new developments are accounted for and the accuracy of capacity and traffic quality estimations significantly improved. In HCM6, these two procedures have not been updated. Therefore, the replacement of the two procedures in HCM6 is recommended. In both HCM6 and HBS 2015, the procedures for calculating delays at shared lanes or shared short lanes are inaccurate and they also should be updated. In most cases, the delays are significantly underestimated. Recently, the authors have developed a new methodology dealing with this problem which can be easily incorporated into future versions of HBS and HCM. In this paper, the theoretical backgrounds of the three new methods are presented and major results are summarized. Compared with HCM6, the advantages of the new developments are highlighted. As a recommendation, three corresponding procedures for estimation of capacity and delay are given for potential use in a future version of HCM.

双向停车控制（TWSC）交叉路口的通行能力和交通性能的估算已成为许多研究人员研究的主题。这些调查的结果包含在高速公路通行能力手册中，例如美国高速公路通行能力手册（HCM）或德国高速公路通行证（Bemessung von Strassen）（HBS）。尽管基本方法相似，但当前的HBS 2015和HCM6之间存在两个主要区别：（a）排名4的运动的阻抗因数的程序和（b）估算这两者的共享短车道通行能力的程序小动作和大动作。在HBS 2015中，考虑了新的发展，并且容量和交通质量估计的准确性得到了显着提高。在HCM6中，这两个过程尚未更新。因此，建议替换HCM6中的两个过程。在HCM6和HBS 2015中，用于计算共享车道或共享短车道上的延迟的程序都不准确，还应进行更新。在大多数情况下，延误被大大低估了。最近，作者已经开发出一种解决该问题的新方法，可以轻松地将其合并到将来的HBS和HCM版本中。本文介绍了这三种新方法的理论背景，并总结了主要结果。与HCM6相比，新开发的优势更加突出。作为建议，给出了三种相应的容量和延迟估计程序，以供将来版本的HCM使用。