Does modifying an edge property delete the edge and create a new one?

I was reading through this [Stack Overflow post](https://stackoverflow.com/a/36544160/1704311), which states that modifying edges will delete them and create new ones with the updated properties instead. In cassandra, this would effectively lead to tombstones due to the deletion.

Your latest documentation however suggests in [29.1.1.1. Forking Edges](http://docs.janusgraph.org/latest/eventual-consistency.html), that this behaviour is only seen when edge labels use `ConsistencyModifier.FORK`.

Which is true? This is the first I've heard of this potential issue; My application is heavily modifying edges, thus I need to know if such an approach is even scaleable.

Also, if the documentation says:

> [...] would lead to conflict.

does that mean that the conflicting transaction would overwrite any results written by the previous one, or simply fail?

Start with the linked Eventual Consistency documentation, especially “29.1.1.1. Forking Edges,” and compare its statements with the linked Stack Overflow answer. Determine which edge-modification and conflict behaviors are documented, then clarify whether conflicts overwrite results or fail and whether Cassandra tombstones are expected.

Written by the indexing model from the issue text.