There's an enormous amount left out of training in that part of the world, from what I gather reading these posts. I'm quite amazed at the number of posters who suggest they've never been taught to properly lean an engine, or the proper use of carburetor heat...but these have been required knowledge for any student pilot from the very early days of flying.
What we have in flight training today is a heritage of inexperience. One low-time, inexperienced pilot teaching another. One pilot is taught by another who knows nothing more than what the low-time pilot before him taught when he got his first instructing job...it's a chain in which each up and coming instructor doesn't know or think for himself, but only repeats and rabbits what his own instructor did...and his own instructor did only what he was taught...ad nauseum.
Even today concepts such as ground effect being a cushion of air beneath the wing are still passed ignorantly from one instructor to another, taught to far too many students...when the truth is much more simple, and much more important to understanding flight.
In your Cessna 152, you may try another experiment some time. Run the trim full up with a power off descent, simulating a glide with the engine out to a landing...see what airspeed the airplane will hold in a glide. Then try it from level with power, trimmed hands off. Pull the power to idle with the trim given three full trims up (grasp the top of the wheel and pull it down to the bottom, three times). See what airspeed it holds. Somewhere between the two, closer to full up trim, you'll find that without any input from you, once trimmed, the airplane wants to glide all by itself. Then do the glide with rudders and see what happens.
This works great in calm conditions. Inside a cloud is very seldom calm. It's usually bumpy, and turbulent. The airplane doesn't want to stay wings level, and certainly doesn't want to hold a pitch attitude or an altitude. It doesn't want to maintain a stable descent, and it usually doesn't want to go straight. Add to this the illusions and disorientation that comes with entry or flight in the clouds, and you've got a recipe for disaster...hence the constant and urgent counsel to avoid flight in instrument conditions until properly certified and instructed.