How strong is an eccentric BB clamp

[Veloo]

I have a 2 bolt eccentric BB and am running a Gates belt drive - a 50 front, 22 rear and a 118 tooth belt. Looking at the drive side, I am able to rotate the BB past the 3 o'clock point with the help of one of those boa rubber strap wrenches. I'm not able to rotate past 3'oclock with my bare hands.

With other gear selections, the belt is taut at 7 o'clock or 2 o'clock.

My question is, can I rely on the clamping of the eccentric BB bolts to ensure I don't slip and rotate when pedaling or should I really use the limit of the belt to ensure no slippage?

[Cicli]

The bottom bracket should hold in place without having to pull its self up against the belt. I ran a frame with the Niner BB for a long time with no issues of slipping or noise.
The recommendation to tension the belt by turning the eccentric the direction of crank rotation is a good idea but not the rule. It should hold in place on its own.

[Veloo]

Test ride this morning resulted in zero slippage. I didn't crank at race level torque but it held. Thanks for the feedback Tihsepa.