On my course, you could get your hair cut anyway you wanted as long as it is within the military hair-cut specifications. I believe the specifications posted
earlier in the thread are accurate. Some guys prefer shorter hair (like a 0 or a 1 clip) others preferred longer on top.
In BMQ, the staff repeats many times that everyone is the same. We dress the same, behave the same, eat at the same time, march the same,
get disiplined the same. During the second week of BMQ, our course had to get in-spec hair-cuts. One section decided to get their hair cut using
a 0 clip. Being in the BMQ mode, everyone in all sections got excited and decided to be the same and asked for the same short hair-cut. It
was kind of the beginnings of platoon teamwork.
In the Farnham field exercises, I appreciated a short hair-cut due to the rarity of baths or showers. It was a winter BMQ so we worn our touques
alot. Most body heat is lost thru the head so a short hair-cut in the heat of summer might not be a bad idea. Its grows back anyway.