First, a buddy is someone I choose to share a dive with.. their skills can be less than, equal to, or greater than mine. This way I can share my knowledge with those that know less, and I hope those that posess superior skills will dive wth me and help me along the way as well.
Once we have determined to dive together, how we proceed defines US as a buddy team. The team should dive to the lowest training / capabilities.
If I encounter a situation, (stuck in net) and realise I am buddy-less, the mistake (issue) came well before getting stuck in the net..
Lost buddy, look for ~ 1 min (or per plan, depending on type of dive). END DIVE!
Engage captain / others, start lost buddy search.
If, when Murphy decides to show his face, I pray that I didn't make the mistake of having lost my buddy as well.