Tolerance in Esri geodatabases is at least twice the resolution and advised to be 10x the resolution (see Esri technical paper 2007: Understanding Coordinate Management in the Geodatabase). This conflicts with the BGT-rules.
Within BGT we work in millimeters (BGT-rule). This also allows vertices to be one millimeter from each other, supported by all other suppliers in the BGT-world. But in a variety of Esri geodatabase management tools, including topology and complex editing tools in ArcGIS Pro, during the cracking and clustering process vertices closer to each other than 5.6 millimeter might (or will) be replaced.
All other GIS/CAD editing products in the market allow for the tolerance being same as or even smaller than the database resolution. We need that too for this registration