Advanced ASL was, I think, an effort to provide the SL savvy crowd with a more complete and better thought out game system, leaving SL there as an introductory tool. In fact for many moons that is what was expected. However, it became increassingly apparent that SL taught many "wrong" principals of ASL, not to mention the counters were all wrong or at least not particularly compatible to the new game.
ASLSK was formulated intended to follow the programmed instruction trend using the current units/counters found in ASL and for the most part compatible rules. Infantry combat was presented first then added levels of complexity in following releases. Perhaps the scenario presentation format within the offers could have been better structured, perhaps even to the point of following and noting the old SL progression technique, to acclimate players to the system however. Where (IMHO) ASLSK fell short was in developing the infantry combat further without introducing the more complex or time/rule intensive aspects of the rules. For example they could have introduced walls/hedges, fortifications and building/terrain levels, all fairly simple concepts but integral part of ASL, but still avoided bypass movement and its inherent ramifications (as they have done with regards to bypass movement) that entails a wealth of special circumstances and extensive rules to cover them.