We have only used the standard Schweizer chin hooks for auto towing 1-26s and 2-33s. We have auto towed Standard Libelle, Diamant 18, and DG 100 with CG hooks over the years. The Schweizers undoubtedly could get somewhat higher if they were equipped with a CG hook. The chin hooks do result in a tendency where the horizontal tail will stall if the pilot pulls back hard on the stick beyond a certain limit. When the tail stalls, it rises, thus pitching the nose down, and actually reducing the angle of attack of the wing. With experience, pilots learn to pull back on the stick to a point just short of inducing this tail stall, which can give the maximum performace climb. If the pilot does not ease off the back pressure and persists in pulling back, a repetitive series of tail stalls, each wth a with pitchdown, followed by the nose pithing up again when the horizonral unstalls, and then as the stick is held back, and then a new tail stall and the resultant ,pitch down. This "bucking" phenomenon is not really dangerous as long as the glider is within design limits of airspeed for ground launch and is otherwise structurally sound ( probably does cause some unecessary fatigue loading to the structure, however). In fact, it might even be considered a usefull feedback signal to the pilot to back off some on the back pressure until the bucking stops, and to check and be sure airspeed is within safe limits. With a CG, hook you don't get the bucking, and can trim the glidet to almost fly the tow by itself in pitch, but you also get less feedback through the back pressure on the stick as to how much loading is being applied to the wings. We generally try to target an appropriate airspeed for a good climb for that particular glider under the conditions of that particular flight, not too fast, which requires lowering the nose to reduce the load on wing and possibly even releasing if at or approaching max placarded auto/winxh airspeed, and not too slow, where a hard pull up would increase risk of stalling the wing near the ground. We use target airspeed of about 50 mph for the 1-26, and about 55 for the 2-33 with 2 occupants. We make an estimated allowance based on the wind speed and wind shear for the tow vehicle driver's initial groundspeed. From there we can make further adjusments for tow vehicle speed using radio communication or between flight debriefings as conditions may change. We never attempt ground launch with any downwind component in wind direction, even in what seem like very light winds on the ground. Any wind shear in a down wind launch will have a very negative effect on climb performance, which is not good if your runway lenghth is relatively short to begin with. "Tension controlled" launches as have been discussed in Soaring Magazine in winch launching articles would undoubtedly be ideal also for auto tows, if not so much for safety as for achieving maximum launch height dor the given runway length and wind conditions. However the tow vehicle determined airspeed target method seems to work well enough, and had a long record of use. Tension controlled auto towing would require much more complicated set ups and a lot more sophisticated testing than what seems practical for our club. We usually reserve auto towing for winter time amusement and skill expanding training in our club, along with a number of times when our only club tow plane has been down. we generally have not made a routine to have simultaineous ground launch and aero tow operations. We also have very little power traffic, limited to mostly our own fly in glidet pilot club members at our glider club owned field