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Two Questons: 1. Sometimes I will see something in the Mishneh Berurah or another accepted halakhah book that is more lenient than most people do. When I ask about this, I am invariably told that this is not our minhag. How do I know when "our minhag" is an authentic one or one of recent vintage? BAsically I have learnt that I can't even study a book like the Arukh ha-Shulhan or the Mishneh Berurah and follow what he says, because in many cases people do differently. 2. On the one hand Hazal say that if you do something that you arenot required to do you are called a hedyot. On the other hand, poskim often say, Ha-Mahmir Tavo alav Berakhah. Is this a contradiction or can these two passages be reconciled?