I have to respectfully disagree. it matters when your running 1"to 4" Ocal in big racks. Price of an expansion joint can be upwards of $400. Not saying every joint needs to line up, all the time everyday, but money is saved in having pipe joints line up on big straight aways. Measure twice, cut once, takes on a whole new meaning.
Not saying it's an everyday occurance, but would be embarrassed if I couldn't get a big rack going, and guarantee it would be pretty in an efficient manner. Guess it all depends on who your early day instructors were.
For the original poster. Know thy bender. String is your friend. 1.57 is your best friend. Keep that no dog close
Don' want no howlers out there!