Yes, and is it possible to assume that Leverkusen were nothing more than lucky last season? I think it is possible to assume that, but at the beginning especially before this season started I really never expected Leverkusen to experience this kind of decline in performance, it means that it seems that there is something wrong with Xabi Alonso, maybe he is wrong in implementing tactics or maybe he did not make any changes to his team so that other teams know his weaknesses which makes them draw more than win, even though as you said last season they were extraordinary which won the title without losing at all throughout the season.
Yes, Leverkusen now have a 7 point gap with Bayern Munich, in the next match Bayern Munich will play against Heidenheim at home and I am sure this is an easy match for them to secure full points and continue to distance themselves from Leverkusen.
I don't think winning the Bundesliga title without ever losing can be called lucky. It was Leverkusen's hard work last season and they deserved it. This season Xabi Alonso's troops are indeed struggling, their performance decline is clearly visible and what is wrong with Leverkusen now is in their fragile defense, we can see from 12 matches they have conceded 19 goals. You can't compete competitively if the defense you create is easy for your opponent to pass.Yes, Leverkusen now have a 7 point gap with Bayern Munich, in the next match Bayern Munich will play against Heidenheim at home and I am sure this is an easy match for them to secure full points and continue to distance themselves from Leverkusen.
And regarding the Bayern Munich match, we will agree that 3 points should be easy for Kompany's troops to get. On paper Heidenheim is not a tough opponent but that doesn't mean they came to lose, unexpected things can also happen.