"Which part of the idea is BS?", ok, will spell it all out for basic clarification...
- reduce power, retrim, hands off the yoke, use rudder only for turns...
Ok, we are flying straight and level at reduced speed; we do not know what that speed should be reduced to or even why, but the nose has pitched down and the trim will need to be adjusted to a more nose up attitude; i think we are flying straight and level again; great...
Now we will turn with just the rudder; great... we are turning, and what is the secondary affect of turning with our rudder? Roll... we are rolling and our hands are off the yoke... What is the primary affect of rolling? Gravity... we are gravitating towards the ground... What is the secondary affect of roll? Yaw... we are yawing into the turn... Our bum is telling us "we are climbing, good, we are saved"... now we are climbing faster, "something does not add up here"... we keep climbing faster, "this is weird, now i am uncomfortable, we are still climbing, my hands are off the yoke, and the power is now at idle, but we are climbing..."... "why is my altimeter dial moving backwards so fast when i am in a climb!".
Again, unless the pilot has basic ppl instrument training practical knowledge, no mars bars for dinner.
It is rare but widespread blanket cloud can form pretty instantly under certain conditions; VFR you have margins to follow to mitigate the chances of being engulfed in cloud without warning. The margins are there partly for this, and partly so VFR remain visible to other aircraft.
The safest thing to do is wings level, straight ahead, cruise climb attitude, check your fuel reserve, mark your current position fix, squawk 66, contact ground for assistance, check for surrounding terrain/obstructions if able.
There are additional things like monitoring engine speed or if flying a csu, manifold pressure to assist in determining transitional climb descend pitch rate changes.
Things go more wrong when turns are brought into the imc scenario.