You're right bayern munich need to be consistent in thier position and also try to win more matches so as to increase the point difference, because for the fact that they have 8points ahead of laverkusen does not guarantee them to be the champion this season. Because they are still in the middle of the season if I'm not mistaken, so anything can happen. As leverkusen is trying so hard to cover the point difference.
Although Bayer Leverkusen is still trying hard to reduce the points gap with Bayern Munich in the remaining matches which are quite a lot, I don't think that it will be easier for Leverkusen to do this season. Because from the current eight points gap, at least Munich has the opportunity to stay at the top of the Bundesliga standings if Munich loses again in one or two more matches in the Bundesliga. So Munich clearly will not be relaxed enough in facing such conditions for now because Munich will continue to try to add points in every match.
Though you may be right, because the possibility for leverkusen to fill the gap is 5% because bayern munich will always want stop that from happening. Though anything can happen so far as football is concern, but I don't think if bayern munich will be so lazy to the extent that leverkusen will just come from behind and take the champion from them. Moreover, If something like this happen I think that should be the worst nightmare ever in the history of football.
However, with the performance of leverkusen I think they're opportune to gain victory in thier upcoming match against kiel who happens to be one of those teams that came out from the relegation zone this season, so I don't even see this team being a threat to leverkusen.