Tennismom and Youarenottheboss, Do you have any personal experience of CC? Your observations seem to be based on what yiu have heard rather than what you have experienced yourself.
There are very sporty boys at CC who thrive on sports fixtures and excel in rugby, rowing, tennis, fencing, cricket, swimming, aikido, etc, benefiting from good facilities and dedicated coaches. However, only 15-20 boys, at most, can be on the A/B teams in most sports. The other 70 or so boys in each year do not Not suffer "ribbing" nor do they feel any less valued nor are they prevented from enjoying sport at whatever level. In fact, if you read the school newsletters, you'll see that the results of D, E, F teams are reported as frequently as those of the A/B teams. Every boy has opportunities each year to represent the school, regardless of sporting prowess.
More importantly, music and drama are outstanding at CC and talent in these areas is celebrated, as is talent in art, debating, chess, math competitions, history competitions, etc. a few years ago, one boy was celebrated for success in cup-stacking...
The school is characterised by bright, energetic boys with a wide range of interests and talents.
As for 11+/13+, my observation from seeing boys at other schools is that the boys at CC are under much less exam pressure. If biys struggle at any point, there is plenty of academic support to help get them on track. The school does not prepare specifically for CE but the curriculum is such that boys who wish to take CE have no difficulty in doing so and, as someone mentioned above, most secondary schools are familiar with the CC curriculum and are willing to take the internal exams instead of or as an adjunct to CE.