This trait is useful, as it is unlikely for even a combat-oriented character to use more than 3 of these skills, and in all likelihood only 2. As such, 20% is "lost" while at least 45% (speech, barter, and doctor) is gained. In Fallout 2, first aid is mostly useless as one can wait indefinitely. This is not the case in Fallout, as all 60% of this is useful. One may also tag their most used combat skills, negating the initial loss and increasing by 5%. In Fallout Tactics, this trait is very useless, as combat skills are always the main concern and non-combat skills are not nearly as important.
Fallout: New Vegas
This trait in New Vegas will boost your social skills (+5 to Barter, Medicine, Repair, Science, and Speech), while lowering your weapons skills (-5 to Energy Weapons, Explosives, Guns, Melee Weapons, and Unarmed). Although this trait seems like it would only be preferred for a pacifist style play, it is not a bad choice for aggressive players either. Most players will usually only use one or two types of weapons, allowing the trait to enable them to use all of the boosted skills eventually.
This skill gives twenty five extra points to skills most characters make general use of, while only taking away five or ten from the main combat skill you use. This equates to more or less a level and a half worth of skill points added to your characters maximum skill point potential.
J.E. Sawyer's Fallout RPG
You're a friendly person and are hesitant to employ violence to solve problems. You have +2 to medic, persuasion, and science. However, your combat sequence is -4.
Your natural charm allowed you to get along with nearly everyone while growing up; you rarely got into fights and spent more time hitting the books instead. You were able to take good care of yourself instead of constantly having to figure out how to survive. Your combat skills start at a lower level, but Barter and healing rates are substantially improved. Barter gets a 25 point bonus. You also get a negative 5 point modifier to starting melee combat skills (One-Handed, Two-handed and Unarmed). This trait cannot be selected with Nasty Disposition.