String concatenation vs string buffers in Javascript

Question

I was reading this book - Professional Javascript for Web Developers where the author mentions string concatenation is an expensive operation compared to using an array to s

Answer 1

Even if it were true and the join() was faster than concatenation it wouldn't matter. We are talking about tiny amounts of miliseconds here which are completely negligible.

I would always prefer well structured and easy to read code over microscopic performance boost and I think that using concatenation looks better and is easier to read.

Just my two cents.