Hello dinohunter1, and thanks for your interest in our work. We worked from the description and reconstruction of Microraptor in the original work by Xu et al (2003). While we did not report aerodynamic effects of removal of the tertials in this paper (coverts are the feathers covering the body), we do report the effects of removal of leg and tail feathers, which can alter typical L/D and stable equilibrium gliding estimates as well as stability and control effectiveness.

There are three things I can mention in response to how the absence of tertials might affect aerial behavior. First, absence would reduce area - generally making speeds higher and impacts faster; for certain birds that must fly to feed (like hummingbirds) molting can have some impact. The impact is less, however, on maneuvering as the remaining feathers are distal. I did some test ones with this and saw smaller changes in the control effectiveness, but did not do enough runs to report it due to limited time. Finally, the distal feathers move fast because the tip speed is like frequency * wingspan; since forces and torque go like speed^2, it is possible to move surfaces just a little faster to compensate for loss of surface proximally. I believe there are folks out there researching wing damage in both birds and insects who find this sort of thing; in some future work I plan to describe some observations of wing-clipped domestic fowl (when clipping wings in poultry, it is typical to keep the distal feathers for appearance sake and to allow the bird something to cover up with); there are also examples cited in the paper where animals without elaborated wing surfaces or any obvious morphological adaptations for flight still possess some ability to control aerial position.

So yes, absence of tertials would affect gliding or other aerial behaviors in some ways... but I believe an animal without tertials could still have a fair degree of aerial maneuvering capability. Thanks for your question!