It's fine to ask I agree but the tendency will always be to encourage and also to be very guarded about particular policies, so a degree of caution is wise. This was feedback I assume, so a little different. What a bonkers policy too....
I was picking up your point about competitiveness in the cycle that you're talking about, which was 2011. It's interesting that the applications to Cambridge actually went down in that pre fees hike year by a significant margin whereas Oxford's were at a record high.
I think it's also interesting for applicants that there are on the whole many more applications per place at Oxford, so that may be something worth bearing in mind for an applicant with a decent AS profile. That and the virtually guaranteed interview at Cambridge, if you think interviewing will be a strength. The Oxford pre-tests might be a deterrent too, for some.
The figures are quite striking: in the 2012 cycle for example:
Cambridge: History 591 apps for 199 places = success rate 33.7%
Oxford: History 1,012 apps for 227 places = success rate of 22.4%
Cambridge: Medicine 1,639 apps for 280 places = success rate of 17.1%
Oxford: Medicine 1,511 apps for 155 places = success rate of 10.3%.
Very roughly, Oxford has 2,000 more applicants each year than Cambridge for slightly fewer available places.
This is a different point from your point about ebbs and flows of competitiveness, but might be quite interesting for someone a little hesitant about their application and with no particular preference either way.