To the OP:
I would second what DCBC said. Here is what I think of as a checklist:
a) Am I completely prepared to do this dive plan? Depth is one element of the dive but so are the conditions (water temp, viz, current, surface swells, surf, anticipated workload, entry/exit, etc.). Prepared means in all ways: equipment, experience/training, physically and mentally. My guidance isn't what a page in the PADI manual says -- it is what can I do safely.
b) Are there any local laws that prevent me from doing my dive plan? (Where I dive, no).
c) IF I am diving with a charter or guide, are they OK with my plan? (I rarely dive with a charter or guide, so not really an issue).
d) Will my dive plan mean that I will not be covered by my insurance on that dive? (Not an issue for me as I am covered at any depth).
e) IF I am a PADI pro, and diving in that capacity, I will follow "the rules" because of liability issues. (Does not apply to me).
f) IF I am a PADI pro, and diving recreational with a buddy or group, I will follow "the rules" because of liability issues. (Does not apply to me).
So, for me, it all comes down to (a)...