first of all ????? ????? can appear in 2 ways, when he comes in “the flesh”, like a ???? he is bound by the rules of a body, and can eat etc. the ???? says he cannot come on ??? because of the ???? problem. however he can also come as a ???? like we say ????? ???? ?????, then he is not bound by all the rule, and can be in more than one place at once.
second of all the ???? to open the door after benching at the seder has other reasons as well the ??? ???? says that it is a ??? ????? ???that was eaten in ??? ??? and was ???? to take out of the house, but after benching they would leave the houses and go up to the roof.
thirdly i can list many things you learned as a kid that are dead wrong!!