B/X Cover-to-Cover - pages B6 and B7

Quick thoughts while I read pages B6 & B7:

• "To choose a class, a player should first look for his or her highest ability scores." - Moldvay was a rabid power gamer ;)  As an aside I always loved playing clumsy thieves, sickly fighters, clerics that are lacking common sense, etc. It is funny how often these "sub-par" characters can sometimes last in a campaign.

• Strength, Intelligence, et al are called "ability" scores instead of attribute scores, stats, etc. The word "ability" is also used throughout the descriptions.

"Strength" is a measure of muscle power and the ability to use that power.

 "Intelligence" is the ability to learn and remember knowledge, and the ability to solve problems. 

etc...

• I noticed a number of times in the descriptions terms (or closely related terms) that become "skills" in later editions - balance, endurance, intuition, knowledge, etc.
• Ability Score Adjustments - "This adjustment shows that a character may practice hard and learn how to fight or reason well..." I always new the option for the 2-for-1 swap but I don't remember ever reading this sentence before. As such I find it somewhat perplexing that Constitution cannot be raised or lowered.
• A very short description about Hit Points and what they are. No talk about them being part luck or divine favour such as found in the 1st edition Dungeon Masters Guide.
• Surprise, surprise... I love the standardized -3/+3 ability score bonuses.
• "Maximum Number of Retainers" - at one time or over the life of a character?

B/X Skills, Actions and Resolution Subsystems

A quick read of the B/X rulebooks gives a list of the following resolution systems (and I may have missed some):

1. "to hit" rolls
2. saving throws
3. thieves' abilities
4. turning undead
5. opening stuck doors
6. finding secret doors
7. listening
8. reaction rolls
9. surprise
10. damage
11. morale
12. ability checks (save vs abilities)
13. evasion
14. foraging
15. spell research and magic item creation
16. becoming lost

These can be broken down into the following basic mechanic systems:
d20 vs target number
1d6, 1 or 2 succeeds
2d6 higher better
d20 under target number
d% vs target number

I think they can also be broken into the following thematic groupings:
"to hit" rolls - combat actions and maneuvers
saving throws - last ditch reaction to an action
reaction rolls - social, non-combat interaction
morale - combat interaction
open doors, foraging, etc - proactive, non-combat, physical, adventuring-type actions
find secret doors, listening and surprise - perception, awareness, intuition, etc.
ability checks - proactive skill-based actions
d% - very granular skills and "holy crap" actions

A quick look at the d20 SRD lists the skills below. Based on the B/X resolution systems, I have given a quick "conversion" of how I would handle each d20 skill-based action using B/X. Of course, each situation may be different and how I may handle each situation may change based on various factors.

Appraise - either roll a 1 or 2 on a d6 or an ability check
Balance - either a dex check or a d% check, maybe a "to hit" roll modified by dex if in combat
Bluff - reaction roll if outside of combat or a morale check if in combat
Climb - a thief ability, dex check or a d6 roll
Concentration - I wouldn't use this
Craft - either an ability check or a d6 roll
Decipher Script - read magic or read language spells, maybe a Int check of a d6 roll
Diplomacy - reaction roll
Disable Device - thief ability
Disguise - a d6 roll or a d%
Escape Artist - a d6 roll or a d%
Forgery - a d6 roll or a d%
Gather Information - reaction roll or a d6
Handle Animal - reaction roll
Heal - healing rules are given in the rulebooks
Hide - thief ability or surprise roll
Intimidate - reaction roll if outside of combat or a morale check if in combat
Jump - d6 roll, a dex check or maybe a d%
Knowledge - d6 roll or an int check
Listen - d6 roll
Move Silently - thief ability, surprise roll
Open Lock - thief ability
Perform - reaction roll
Profession - ability check or d6 roll
Ride - I assume everyone know how to generally ride a horse. Actions that may cause a rider to fall off or lose control of the horse are reactions to other actions so I would give a saving throw.
Search - find secret doors
Sense Motive - the players can decide if the trust someone
Sleight Of Hand - a thief's pick pockets or maybe a dex check
Speak Language - either they know it or they don't
Spellcraft - maybe give a magic-user a chance
Spot - listen or find secret doors
Survival - forage or becoming lost check
Swim - given on page X51
Tumble - maybe a dex check?
Use Magic Device - just use the rules as given in the rulebooks
Use Rope - a d6 roll

EDIT: One thing this shows me is that you can do everything that a skill system can do just using the B/X rules.

B/X Ability Scores

From page B6:
A couple of things that strike me:
1. They are called "Ability" scores instead of attribute scores, stats, etc. The word "ability" is also used throughout the descriptions.

"Strength" is a measure of muscle power and the ability to use that power.
"Intelligence" is the ability to learn and remember knowledge, and the ability to solve problems.
etc...

2. I noticed a number of times in the descriptions terms (or closely related terms) that become "skills" in later editions - balance, endurance, intuition, knowledge, etc.

Ability scores are more than just the raw characteristics of a character. They also reflect the ability to harness these characteristics into actual abilities. You don't need a swim skill to know if the character can swim across a raging river. A DM can reasonably determine if a character can swim based on his background. He can take a look at the character's strength and see of he has the ability to harness his strength to swim across the raging river or he can ask for a save vs strength or any other mechanic to let the dice decide.

Ability Scores + Class give all of the skills anyone could possibly use.