I have my hives in the garden and three quite close to one another. As said the main thing is you need to think about space for manipulating etc. Also I found that the close proximity help instigate robbing this year by my strongest colony. That said not many have the luxury of limitless space to be able to spread them about in an ideal way. One thing I haven’t noticed is drifting at least on any noticeable scale. Think bees are pretty good at finding and keeping to their own homes unless they have reason to be in another one that is
There was often a theory quoted that end of row hives did “better” by gaining drifting returning foragers increasing yield and also workforce.
Can’t say I have observed a consistent positive correlation based solely on end of row location. Anybody else?