The stellar run we were on was not due to us playing good football as a team. It was solely due to Jack being in excellent form and pretty much single-handedly getting us promoted. If we really were playing good football as you say, then we would not have looked poor like we did when Jack was absent in the championship, or in the prem (vs Wolves for example), and when he is present but has no influence in games due to being marked by 2 players. Many fans are mistakenly thinking it was Smith due to whom we were playing " good football ".
Look at Sheff Utd for example, they have been playing good football since they were in League 1 and have continued that effective and attractive manner of playing into the premier league, and hence they are doing well, whereas we are struggling as we have no style of play due to Smith leaving his coaching staff at Brentford and not employing a competent coaching staff at present.