This is something lost on many trainees, beginners and otherwise. Someone asks a question like “what angle should I have my hand turned when I do dumbbell presses”, and when you ask them what their goal is, they simply say “get stronger”. If your goal is to just get stronger, all you need to worry about is if you are getting stronger in your movement, period. Minute details will not derail a big picture goal like getting stronger, this is simply a question of dedication and willpower.
Looking at this from the other perspective, having a specific goal necessitates putting on the thinking cap and getting into the weeds. If one says that their goal is to increase their lagging outerquad development by 1 inch in 12 months, and then ask if they should use leg press, it would open up a million follow up questions. What sort of leg press, what protocol, what angle will you point your toes, what are your rest periods, etc.
We may need to talk
We are arriving at a bigger issue here, and that is the reality that many beginners refuse to accept the reality of just how simple it is to get bigger and stronger. To admit this is to admit that the fault was in us for not trying versus not knowing, for ignorance is excusable, but laziness is unforgivable. Thus, new trainees seek information to justify their lack of gains and stumble upon the works of advanced lifters who are well beyond the realm of beginner gains that need an incredible degree of complexity in their approaches to elicit gains. The reality is, if you just do something, you’ll be fine, whereas if you stall and flip flop, you will make no progress.
Sometimes, it really is simply that input equals output. The more you give, the more you get (as long as you make sure to eat to match your training). You don’t need to worry about the angle of your hands or if your thumb is on top or on bottom of a barbell, or if you are pressing with the edges of your hands or your palms. You aren’t going to trick your body into growing by changing the angle of a movement, you have to actually do what you want to accomplish. Your body doesn’t lie to you, and if you want to bring up a muscle, actually strive to feel that muscle when you train, don’t just rely on mechanical changes to accomplish your goals.
Maybe NOW I'll finally be able to hit my triceps
Additionally, you aren’t going to trick your body into avoiding injury through some body voodoo. Injuries just plain happen. There is no safety in this world, and you put yourself in more danger driving to the gym than you did once you set foot inside it anyway. The joy is that you won’t see the injuries coming, and that they will be a learning opportunity, but instead of sweating if a 33% degree on the incline bench is a receipt for injury, just start hammering the basics and growing. You will be much further ahead than those who are sweating the small stuff and spinning their wheels.