My back injury wasn't caused from MP, it was caused from overzealous DL'ing with bad form, which in my defence, I was fairly new to lifting back then and lacked the experience to know better - some of us just have to learn the hard way unfortunately. Hindsight is a wonderful thing...
Generally yes, but also no. Correcting technique doesn't automatically make you strong, you still have to train... and think about what 'form' is for a moment. Correct 'form' is generally the most efficient way to perform a movement or action, that doesn't mean it is automatically safe, for example, if a novice overloads the bar and tries the lift with "good form", injury may still occur because they are weak. On the flip side, doing movements in "bad form" but in a controlled manner to build strength in compromised position/less-efficient movement, aids in strengthening the movement when done in correct form, for example, "good mornings" to assist squats etc.
I disagree. CBF explaining why but as a simple test, try and do your seated press weights standing and tell me which is harder.