I sometime wish instructors had higher expectations to be honest. I'm doing the CPL/MEIR shortly and despite mentioning this and asking for a higher level of scrutiny when I do take a trip with an instructor, I rearely seem to get it, maybe its because to scrutinise student flying at CPL standard you need to have done a more advanced instructor course? Not sure. As one of the other posters remarked, you usually hear "yeah, you handle nicely" or "no problems here". Yet, I know I haven't performed as well I was wanted to and would have liked a more thorough de-brief.
My ab-initio was with the RAF (UAS - yes I Know I was very lucky and spoilt at an early stage) and the required level of performance was very high and you soon got told (shouted at actually!) if it wasnt good enough. It would be good if that level of scrutiny was available to those who wanted it in the CAA FI world (not referring to the verbal abuse obviously- although personally I found it very effective!). The average FI, quite rightly obvioulsy, is content with a performance which gives him/her confidence you're not going to kill yourself....just wish the level of scrutiny corresponded to your hours to some extent...i.e 250hrs..you should be able to handle X so lets see how you do..
Not having a go at FIs by any means..never had a "bad" FI - they're a credit to the industry and certainly its backbone.
I have sought more advanced instruction and have eventually found some FTO's offering it, but it would be great if I could go to my club and ask for a CPL style instructional flight without getting a funny look.