Before you surrender, remember it only takes one Ace or a backdoor to win a "lost" game
Some disadvantages are insurmountable, sure, but more often than not a game is surrendered when your team's spirit is broken rather than when the game is impossible to win.
Stay positive, and don't give up so easy. A single Ace or a tricky backdoor while you prevent the enemy B can turn the most impossible game into a close win. People get complacent most when they are ahead too, so they usually don't use their full advantage and start making bad calls.
Your LP is worth it, isn't it? A close match is more fun than a landslide victory anyway.
for a good backdoor but again try explaining this to a team that doesn't even understand why "facechecking" is a "bad idea"