Victor - if only planning is that simple.
Unfortunately Planning decisions are that simple. Once the college started to discuss selling the Hibbert lane site to Walmart, and at that point their consultants would have spoken to SMBC's planning dept., they took the lid of Pandora's box. A likely scenario is:-
College's consultants talk to SMBC planners.
1 SMBC planners look to see if Walmart application would pass the "Sequential Test", and decide it would.
2 SMBC planners try to see if there is other land within the District Centre that could accommodate a Supermarket thereby thawting Walmart's application.
3 Chadwick St. option ascertained as land possibly available.
4 Chadwick St. marketed as potential development site.
5 Preferred Developer appointed for Chadwick St.
Hence the position we are in now. All as a result of the College's decision not to try and discuss this with our elected representative's before making any decision.
Please note these are only my thoughts on how this whole thing developed, I haven't got access to any more privileged information than any other member of the general public