Our party enters the room. Three goblins throw javelins. One hits my fighter and does 4 points of damage. My PC dies. That's it.
OK. First, my party would be listening at the door. If we heard them, we'd try to go in guns blazing and hope for surprise or at least initiative. If we failed, we retreat to a corner and make them fight around it, or slam the door and spike it closed. (Of course, we use the same tactics in 3.5e as in AD&D on this stuff.)
We walk down the hall. Pit trap drops us 10'. My magic-user takes 3 damage. My PC dies. That's it.
The monk or thief was going first, and using 10' pole, everywhere. Slow, but effective. The MU is NEVER, EVER, in front or in back. The approved marching order is: point-man, killer meatshield, secondary meatshield, MU, cleric, tertiary meatshield. Protect the MU . . . if you can get an MU who survives, the whole party is rocking. (Again, we go similar marching orders in 3.5e, but we have dispensed with the 10' pole -- why pole when you can just roll?)
We find a treasure chest. If there's a trap, my thief has a 15% chance to find it. Open chest, fail the "DC 17" poison save. My PC dies. That's it.
Everyone stands outside the room, while the thief smashes the chest with an axe. If there's a poison gas trap this time, oh well, get a new thief. (Or, in 3.5e, have another PC start taking Rogue levels.)
BTW, I've always had all PC's start at 1st level, or take over an existing NPC. We're almost always had more characters than players in a party, so that a player with a dead PC can take over an NPC who's already a party member, and so that's there's enough characters. More often than note, the DM has also run a PC . . . a normal PC who can (and often will) buy the farm, not the infamous "DMPC of uberpower" that people hear complain about, but I've never actually seen.
And the thing about starting two parties and combined the survivors to get something viable, plus having a large party of about 8 PC's so you can lose a few . . . that's how we survived the G123/Q1 series!
Of my two characters who survived, one was mine from the start, the other was an NPC I took over . . . two other characters (1 mine from the start, 1 NPC takeover) bought the farm. So, I dunno 25-50% survival rate, depending on how you look at it. Seems fine to me!