[linux-audio-user] help needed with JACK options

Greetings: I'm preparing various materials regarding ALSA and JACK, and I need some help understanding some of JACK's options. I've consulted the JACK FAQ and the jackd man page, the existing explanations are clear enough as far as they go, but they don't actually explain *why* a user wants or doesn't want to activate certain options. Namely: 1) What will the -m and -u memory options do for a normal user ? Under what circumstances is it appropriate to use them ? What exactly does it mean to unlock a GUI library's memory, and again, how/when does it benefit the normal user ? Are there reasons a user should not enable these options ? 2) I understand audio dithering conceptually, but what would be a typical situation when I would enable it in JACK ? 3) Is there any particular good reason a user would *not* want -R enabled ? 4) Regarding the "Force 16-bit" option: When would a normal user want to activate this option ? The FAQ and man pages are informative enough for the remaining options. Any help with the questions above will be hugely appreciated. Best regards, Dave Phillips