He said he picked it for practical purposes. That’s convenience. Your opinion of what a word means is no more factual than your opinion about the accuracy of the dispatcher clocks.
Practical does not mean convenient. Here are two definitions from the dictionary that are applicable to Bowles’ use of the word:
1. (of an idea, plan, or method) likely to succeed or be effective in real circumstances; feasible
2. so nearly the case that it can be regarded as so; virtual.
And a phrase from the same dictionary:
for all practical purposes — virtually, or essentially.
"Zimmerman had become, for all practical purposes, an arms smuggler"
You two seem to have a problem with the term “rational assumption.” Just because it is an assumption does not mean that it is arbitrary. In fact rational is an antonym of arbitrary (opposite meaning).
Now, if you have a problem with how Bowles derived the time, and can demonstrate that he made a mistake, lets hear it.
Arbitrary does not describe Bowles’ method by any sense of the word.
