I'm considering Nitto 123aa for a deep drop bar for track use. (Not many alloy bar options to fit my 26.0 stem). I noticed that the range of widths available is narrower than I expected.

Is a narrower bar somehow preferable for bunch races (to squeak through marginally narrower gaps)? Or is it because NJS bars are made for a market of slightly narrower racers? (European brand track bars are generally 40cm or wider.)