Pros/Cons Initial agitation

Assuming I'm using a 5 minute presoak and I'm agitating 10 sec each minute, or, in some cases 10 sec each 3 minutes...

what are the pros and cons of a 15 second initial agitation vs a 30 or 60 second initial agitation? (other than a better chance of securing eveness of development.)

thank you.

The Film Developing Cookbook goes into detail on this subject in detail. I always use at least 30 seconds for the initial agitation if I can fill the tank quickly, and 60 seconds if it takes 10 seconds or so to fill it. I have no observations to offer on alternative methods because I learned these times and have always gotten results I liked.

- Randy