Hi George,
I think you are on the money.
1) High production, one side presented at a time, multiple bars and all at 45 degrees - all spot on.
2) length of material irrelevant, this will be controlled on the saw prior to presentation to machine. It would need an end stop to control the "bite" at the 45 degree mitre. Too shallow and we would get a "flat" end or a short 45 degree. Too deep and we would get the tenon sitting proud of mitre. We need a perfect clean corner. If we presented a 4 x 12" bars to the machine and the cuts are perfect, then we would obtain a perfect 12" square frame.
3) We do different profile sizes. the first number identifies the depth of the profile and the second number the width of the profile. 18*44, 38*35, 47*35, 50*35. Depending on how you present the profile to the machine, the base of the first number would be the datum. This would allow centre of bar to be established and the width would always be cut at 45 degrees. In order to get the spacings for the tenon / mortice to fit in at the corners, the machine would need to be adjustable (up or down) for the opposite side to be machined, therefore allowing a perfect corner (i think you are with me on this so will leave itr there)
4) One pass is sufficient as there is not a lot of meat to be taken off the mitre at any one time.
5) I would think the operator would be there. He would be loading and unloading the machine. If we can find a way of hopper feeding machine and securing the presented bar, all the better, but this may be the next step.
6) From a single machine I would need to get a minimum of 8 - 12 finished bars (double this for individual end) per minute. I have no maximum :-) . This should be easily attained if 4 or 6 ends are presented to the machine at one time. (I am not adverse to going for more than one machine as long as we get the first one working to spec.). The machine on the video link does 8 per minute, but it is only presenting 2 bars at a time and doing both ends at the same time. I could accept this if we were looking at doing both ends at the same time, but think a different presentation and doing one side at a time would increase speed considerably.

now you have finished teasing me, how far have we got with the prototype :-)

If you need more info, just shout.
cheers
les