Abe Laboriel also mentioned this experience he had once. As an experiment, he gradually shut off his amp to see what would happen. The sound guy didn't know about it, but after the set he goes, "Man, you've never sounded better!", and from that point on Abe made it a point to make it as easy for the sound guy as possible to get a better balanced mix.
I think a lot of people agree on the problematic nature of too much stage volume and placing the vocal mics right in front of the drummer which would cause too much bleed, etc.
It's mostly for the practical nature of mixing in a live setup.
Of course, it's often scary to leave your sound at the mercy of another person, but overall, as much as I hate it, I've come to believe it's for the better good.
But yeah, I DO LOVE nice loud stage volume for my own pleasure.
I picked up the minimal gear ethic as well from LA session drummer Voyce McGinley since the gigs 3 times a night. He has to move quickly and never brings too much stuff.
For me, my LMII, 1 or 2 Aguilar GS112s, and my Nordy can cut 95% of any gig out there, any style.
Another plus of the Ashdown is that it's not super heavy either (but sounds so thick!), so I'll bring that for other gigs as well, ones requiring my exclusive use of the P-bass, which is what the OP wanted to know