That's because Skills and Powers was pretty broken. The subabilities broke it the worst, like the division of Strength into Muscle/Stamina. If you had a fighter with 17 Str, you could split the 17 as 19 Muscle and 15 Stamina. What this did was boost you way past all the Exceptional Strength levels right into attack and damage bonuses for 19 Str. IIRC, 17 Str was +1/2 and 19 was +4 attack and either +7 or +9 damage. A HUGE unbalanced jump, especially since none of the PHB races had Str bonuses allowing for a 19 Str at creation, 18/00 was the highest possible. And Stamina? It just affected carrying capacity and encumbrance.
That was the single most egregious piece of imbalance, though several subabiliites were almost as bad. The Int subabilities had one that affected wizard spells and another that affected NWPs IIRC, so most players of non-wizards just used the spell one as a dump sub-stat to boost their NWPs. I think Dex had some breakage as well. I didn't mind the point-based character creation, though I think some hated it as a GURPSification of D&D. Even that though, probably needed some DM policing to maintain balance.
IIRC the Int sub-abilities were actually fairly balanced. One side was like reasoning and the other memory. Memory effected the max spells known per level, logic the %chance to learn a spell. But yeah the strength divide kind of wrecked any chance of those ever being used in my games. Lots of things in skills and powers were good though, and combat and tacitcs and spells and magic had loads of awesome material.