Honestly I need to know. I also am learning to acknowledge that lux's deaths and item build is my fault. I should have flashed+teleported to save her 3 man tower dive and taught her how to build lux and,most importantly,how to keep calm when you don't get a blue buff.
Focus objectives and ping like a mfer. That'll do it.
Just for clarity: 4v5 (or any similar cases) is when you have a teammate missing from the teamfight. If lux is present in teamfights, she can still snare enemies and throw out a shield. She can tank the enemies' abilities which are cooldowns that your team can take advantage of. Yes, her build might not give her any dmg but if shes participating, then don't count her out.
Now, for cases where you're one teammate shy of the enemy, its the same idea as playing a 5v5. You fight only favorable teamfights and avoid all others if possible. The only difference is that you lack that 5th teammate which prevents you from making certain decisions. The game may be tougher but its certainly winnable.
