The subject of 'proofs' being what they are begs the question of who needs to know, what is it they need to know and to what degree.

The Adventure II group came and a certain degree of proof was proffered before their eyes. The degree being determined on what they most needed to know and see. There are others who we've indulged with such offerings.

Some time back, we deemed a proving to be in order for a certain group. We felt it also had to be dramatic in a way that left deniability or rationalization as a non sequitur. Old One and I discussed the matter and from their number picked five men. They were picked up via dimensional door. This was done slowly to allow the many witnesses to the event to 'see' precisely what had happened to these men.

At base, Old One took them on a brief tour which included a trip to the garage to see the many ufos parked there.
They were impressed AND they were full of themselves and their own images of self importance as well. When they were returned, they began calling themselves 'The Chosen Ones'. You see, we didn't pick up their highest, brightest and finest. Instead, we chose their worst. These were little men who made their livings tearing down the good and innovative work of others. They felt themselves elevated in these poor life endeavors and used this occasion to confirm (in their own minds) that they were truly elevated personalities.

We chose their worst because IF these particular men returned singing the same tune and giving voice to what they'd seen - their superiors (who well knew them for what they are)  would find their testimony credible.
They were returned in the same fashion they were taken and within the gaze of many.

We also indulged the deliverance of a gift, actually five copies of the same thing - a device. A heating element was placed within a plastic ball with a touch pad on the side. Activated, the device would give off heat and light up to 80 degrees without generating heat to the casing.  It would be great on a camping trip. However, I'm certain the things are now locked in a vault.