It is true that a significant portion of the IIM population is engineers and a sizeable chunk of these are IITians - can be expected, given that they've been funnelled by the two of the world's most rigorous entrance procedures.
Is the proportion of engineers in IIMs on the rise?
YES, but then the proportion of Std 12 students aspiring for engineering streams is also on the rise. Also, US Engineering schools of late have not been too generous with schols for MS / PhDs, even to IITians, which is why the recent IIM batches have also been seeing more IIT Comp Sc / Elec students, who'd earlier have chosen to specialize in tech areas.
Is CAT heavily biased towards engineers?
Don't really think so... The quanti is Std. 9-10 level. The DI section is very much crackable with adequate practice. In fact, B.Coms, Eco grads and CAs would probably have dealt more with those graphs, tables and pie charts than engineers.
So, the thing to do right now, whether you are (or are not) an engineer, would be to identify the section(s) that you are weak at and iron them out with disciplined practice and a VERY POSITIVE ATTITUDE.
