Many times there will be a person, davening an inordinately long shome esrei. Is one mechuyav to wait for such people to step back from their shmone esrei before passing in front of them?
If you have a need to step back there are a number of options. There are opinions that if the person davening is not straight in back of you, but only to the side, then you can take your three steps back, in a way that isn’t crossing in front of them. If you are really stuck, then even if he is directly in back of you it is permitted as long as you are not cutting in front of him, but taking your steps away from him.
There are also some poskim that say that a person that is davening an exaggeratedly long shemona esrei that it is permitted to walk in front of him, however this is not the opinions of the majority of the poskim, but if you are stuck you have what to rely on.
Eliyahu Rabba O:CH 102-8, Aruch Hashulchan O:CH 102-11, M:B 102-15,18, Ishei Yisroel 29-7 in the name of Chazon Ish, Daled Amos Shel Mispalel 2 5-6 in the name of R’ C. Kanievsky shlit”a in the opinions of the Eliyahu Rabba. Maharsham 102 says that it is permitted walk in front of a person davening in the aisle because he doesn’t have the right daven there, other however argue on this. There are poskim that say that according to the Maharsham it would be permitted, since he doesn’t have the right to daven so long, in a way that will disturb others, therefore it is permitted to walk in front of him.