"I studied for about 2 or 3 years." is natural while "I studied for about 3 or 2 years." is not. Notice that the time period length sequencing is from shortest to longest.
Yet, in this audio clip at www.bbc.com the sequencing is longest to shortest How Japanese Police Confront Violence at the 20-second mark you can hear in the background the officer say
警察学校に一年もしくは半年...
(1) it is natural to list lengths of time in reverse numerical order?
(2) ALSO, notice that he just said "一年" instead of "一年間" which contradicts my understanding.
I definitely would have said:
"警察学校に半年もしくは一年間..."
and this is definitely unnatural, correct? Both cannot sound natural?
What about "2、3本ぐらい飲んだ" vs. "3、2本ぐらい飲んだ"? Which is better?