Yea that's B2's warranty statement, and similar to many.
We are always here to consult and assist in being sure the electrical is setup proper and sufficient to protect your investment, ensure reliability and most importantly, get the best performance out of your setup.
This model per B2's recommendations is not suggested to run at under 1ohm.
If you are wanting to drop the ohm load way down, the R series amplifiers is the line you will want to look into. Zero.5R, Zero.7R, M12R, & M15R
We, and many from our team run the R series amplifiers wired very low (sufficient electrical of coarse) in daily applications with no problems.