Sorry, I would flag this in a code review. It's too easy to skip past this visually. Explicit if statements make it a lot more obvious what's going on. This is too much syntactic sugar.
You must not do a lot of C# code reviews? This syntax is used in every codebase. In fact if you don't use it Visual Studio will underline it as "code can be simplified" suggestion.
I work almost exclusively in C#, and I do a lot of reviews. I'm familiar with the syntax, and I use it. It's the assignment version that I'm talking about here.
You've never seen something like this?