VVTI w/ Aftermarket Cams, Practical Experiences?

Is there a way to somewhat roughly calculate overlap Valve-to-Valve clearance in engines with VVT on the intake and exhaust with high duration camshafts?

I can imagine a scenario where it might be possible to advance IVO far enough that the lifting intake valve interferes with the closing exhaust valve, but I don't know if there's typically enough adjustment at the gears to make it a problem. Is this an actual concern? How do tuners deal with this short of a teardown and testing on the bench?

The engine in question is a VQ35 with Tomei 272's Procams. The cams are perfectly fine at factory valve timing but the people at Tomei can't tell me what the VtV clearance limits are and they didn't tell me not to worry about it either...

This is a real concern with aftermarket cams with a VVT system although most of the mild upgrade camshafts are designed to offer no interference with the stock VVT system. My personal belief is that this is something that needs to be checked and confirmed (and corrected if necessary) when the engine is built. We want a situation where there is zero chance of valve to valve or valve to piston contact regardless of the cam timing and it needs to be checked at both extremes of the mechanical cam timing movement.

We can't rely on the cam control system to avoid potential damage to the valve train as we may not achieve good control of the cam position at very low rpm where we have limited oil pressure, and what happens of the system fails for some reason and the cam ends up on a mechanical stop?

Thanks Andre. I'll be leaving the cams alone! Teardown isn't an option at this point.