we can share smerit each other with your comments that you think are good quality post. I think in this case everyone doesn't mind because we help each other. because usually just rank FM upward get many smerit (just my opinion)
That is considered as abuse. You should not exchange merits with each other. This can also be seen as a sign as both accounts are operated by one individual and those accounts may get tagged.
I think it doesn't matter if we gives a merit each other provided that the post has good quality post criteria. Because sMerit is made to encourage someone in this forum to create a good quality post. Unless if we giving merit each other to the post which considered spam, and the post does not provide an information be preconcerted those account will get tagged.