My favorite stupid unit of measurement is “A gram of protein per cm of height” for protein intake for very overweight people who have no idea what their lean body mass is or should be.
It sounds ridiculous but for 90% of people it puts you within 10% of correct and usually errs on the high side.
BCAA’s are essentially bullshit 99% of the time because if you’re getting adequate complete high quality proteins from food (including whey or quality plant protein shakes) they contain all the amino acids your body can use.
Honestly, the flavor is all down to the brand. But water just gets boring as shit if you’re drinking a lot.
Fundamentally you’re right. If you get absolutely everything 100% scientifically perfect for you, your circumstances, your genetics, etc you will always see better results than the person eyeballing it. But its like 200% more effort for an extra 25% gains, the minutiae of this shit goes as deep as you care to look and thats what drowns a lot of new enthusiasts.
Sometimes I buy a jar of those not because I want to supplement my aminos, just because plain water gets fucking boring.
Its a pretty common unit when it comes to discussing dietary protein around bodybuilding and fitness because 1g per lb is a super easy conversion for people to remember. Its kind of the golden number because even for people not getting the best sources of protein 1g per lb almost guarantees anyone other than edge cases and steroid users are getting more than enough to support optimum growth and recovery.
Creatine is LITERALLY the only supplement that almost everyone and every study agrees.
Anything else the answer to “Should I take…” is at best “It depends” and in most cases “No”. Its the only one if people arent taking it I’d ask “Why not?”