I echo Bruce’s observation that people, realizing that they either cannot fit their bike on a wheelbender, or that it’s very difficult to use their U-lock, end up doing other things that are less desirable! They often end up parking parallel to the rack itself, blocking nearly all the spaces and mostly defeating the purpose of the rack. Or, they lock up to something else entirely – a tree, railing, signpost, etc – that might actually block egress paths and/or break fire codes.
At WMATA too, the inverted-U rack is now our gold standard, and we use APBP guidelines for placement and clearance guidelines. We figure 2 bikes per rack with proper clearance, and inverted-Us are a great way to encourage cyclists to park securely and efficiently.
Good luck!
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