What Billy Goat says! And to expand on that...
Although it is a term widely used, even, regrettably, by CAA, there is no mention of "see and be seen" in the ANO. The reality of VFR flight in Class G, particularly in visibility down to 1500 metres, is more like "see if possible, hope to be seen, keep your fingers crossed and utilise traffic information to supplement the aforesaid".
The concern of some controllers is that the provision of BS will be considered inadequate (specifically as required by CAA, with only very generic TI), more VFR flights will therefore request TS or even DS or PS, with resultant increased workload.
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