Ijtehad by a layman to choose a madhab?

When I was 10/11 I used to pray in both hanafee mosque and shafaee mosque as both were around 200 meters from house in opposite directions. Since as a layman I dont know which madhab to choose. Are the people who say adhering to a madhab is obligatory for layman, are inadvertently asking me to do ijtehad and choose a madhab?