You know what I just realized? Black Dougal of B/X fame had an Intelligence score of 18!
Being a B/X thief in Tom Moldvay's Basic set means the character is a human...there are no other types of thief in the Basic rules. And yet when Black Dougal hears muttering voices listening at the door of a dungeon chamber his character asks:
"Do I understand them? I speak Common, Orc, Goblin, and Elvish."
Human adventurers in B/X are limited to the common tongue in B/X unless they have a high INT score. In order to have three (3) bonus languages, the thief must have an 18 for his Intelligence score.
As a 2nd level thief, one has to wonder what his DEX is that he would retain such a score (in B/X, one may raise his or her prime requisite by reducing STR, INT, or WIS). I would figure it to be at least a 16 if not an 18. Black Dougal would appear to be no slouch in combat given his survival in the fight against half a dozen goblins later in the example (and in melee, too! With 2D4 hit points and nothing but leather armor to protect himself what were his STR and CON scores?!).
Interesting...of course, none of this does anything to save him from a poison needle trap. Felled by a failed saving throw, a 2nd level thief with 18s across the board has the same poison save as a 1st level character with a 3 in every score: 13. That's a 60% chance of death for the player character, and we can see that with those kind of odds, well, the house generally wins.
Poor guy. He just wasn't smart enough!