Not having been a part of the IRC discussion, I'd value a brief post to elaborate on the goal of this system if it is something more than just a way of balancing that advancing skills (in real life) is not equal for all skills. Improvement in some skill is more costly than others. While complete true, this is also subjective. What is an EASY skill and what is a HARD skill may be reversed for two different individuals. Take the Jock and the Geek. Pole Vaulting for the Jock may be a EASY skill while Computer Programming is HARD. But for the Geek Computer Programming is EASY and Pole Vaulting is HARD.
Learning can occur with most skills in one of two primary ways: (1) experience - using the skill in the situations in which the skill normally applies; and (2) training/practice - studying the skill under structured conditions (such as a practice field, classroom, gun range, etc.) Some would also argue that the experience points received may differ between the two methods of skill improvement. I'd argue that current learning theory suggest that if the quality of the experience of the two learning methods is equivalent, then the level of skill advancement would be equivalent.