Multi-wing alignment is interesting to say the least! One thing I picture in my mind is the downwash of airflow trailing a wing. Associated with that is an upwash at the LE of wing. A multi-winged airplane needs to have all the wings aligned with the airflow going over and around them. If the wings have no stagger then the wings can 'make do' with no need for differences in incidence. You can visualize that a fwd stagger will cause the need to have the lower wing(s) aligned with air that is moving downwards as well as backwards relative to the upper wing(s). Vice versa for the negative staggered jobs. The effect is to make the wings stall as a unit. What we are attempting to do is actually have all the wings' lift be equal. This only works for one 'ideal' airspeed because the air is compressible and the 'alignments' change with speed.

I have a Top Flite SE5 that I'm thinking of building very soon. I built one >20 years ago. It was a great flying machine! This one will get a full set of fittings from Joe at Proctor in lieu of those goofy 'z' bend rigging wires. I bought some 'Smooth-on.com' rubber compound for making 'tyres' in dull white so that'll make it even better! I'll experiment making the 'beach ball' tires for my scratch build Vampyr sailplane. You can find it on RCAerotowing.com site. Keep up the great work on you Albi two-holer!