Now, here's an arguement waiting to happen:
1. FR never use CWL as a diversion due to ancient history...
2. BHX is [almost] equidistant to BOH to divert to, so why CWL?
3. Get over it: CWL+BRS are convenient for each other diverts - simple!
p.s. Probably, the fuel uplift at Venice [Treviso] wasn't enough to; (a) cirlce @ BRS; (b) divert to an airfield further away.
...less negativity. Thanks!