It's a really good performance so far showing a bit of little improvement in the team's form based on their two previous games drawing Aston villa, winning Tottenham and currently leading by 3 goals to nil against Westham in the just concluded first half, a game they have gotten all the advantage to win without doubt.
However, Chelsea's victory looks ordinary because West Ham have suffered several heavy defeats this season, from Arsenal 0-6 and the most surprising was losing to Fulham 0-5, so it's not entirely because Chelsea played very well but it also helped because West Ham was very weak. In fact, they are the team in the top ten with the most goals conceded.
Is Chelsea experiencing progress? I don't know for sure, but they have the opportunity to play in one of the European competitions next season if they continue to get three points in the remaining games this season.