I also want to point out that switching techniques to one that's easier in a given situation is only easy if you know how to do it. When I was 4th kyu I found that extremely difficult! You don't automatically see the opportunities, let alone see which one will work best. I totally agree that it doesn't make sense to always do that, but it's still an actual skill and takes work to learn and doesn't necessarily come easily or automatically to everyone.
It's also a bit dicey if uke is also relatively inexperienced, and particularly if he/she seems to be locked in to the idea that things will go according to a certain script (as seems to be the case here - uke knows what's coming). Switching the technique calls for different ukemi, and unless uke also has the skill to switch, he/she is more likely to not take proper ukemi and be injured.