I'm actually based in London rather than Manchester, but stayed there last weekend. I noticed some unusual behaviour planning running routes and while using StreetComplete/SCEE and decided to take a closer look.

In the last year, there was a Map with AI project using a task manager to add pedestrian infrastructure in Manchester (and in several other cities in the UK and US). While this is a good idea in principle and could provide better routing for pedestrians and those with mobility or visual impairments. In practice having separate sidewalks and crossings added as a checkbox exercise by inexperienced mappers with inadequate supervision and review can produce results which are worse than if nothing had been added. Typically, we end up with mis-mapped crossings, crossings at a crossroads where 8 sidewalk ways and 4 crossing ways share 4 kerb nodes (causing routing along edges which do not cross roads to traverse misplaced kerbs), unconnected/dead end sidewalk segments, separate sidewalks added to minor roads with no crossing infrastructure, and pretend crossings added in an attempt to make the preceding item "work".

In this case, it was one or more MwAI users who added incomplete separate sidewalks parallel to Store Street where it passes in a tunnel underneath the forecourt of Manchester Piccadilly station. They failed to add appropriate layer or tunnel tags to those sidewalks and must have ignored editor warnings about crossing ways. This was compounded by VLD292 simply connecting those sidewalks with that of Piccadilly Station Approach without adequately checking aerial or street side imagery to establish whether they were physically connected, which would have confirmed that they are not.

Pedestrian mapping at major transport interchanges in particular needs to be done carefully by experienced mappers who actually care what they are doing. A missed plane, train, or coach resulting from failing to take a short-cut which does not exist could be very expensive and inconvenient.