Those with airplane training will be familiar with Ground Reference Maneuvers which teach students very accurate maneuvering with solid airspeed and coordination control at low altitudes despite the peculiar visual cues found there. Those with glider-only training will not be familiar with GRM's since they are not practical in glider trainers.

GRM's are flown at "pivotal altitude" (Search web) which at 55 knots ground speed will be a little under 300'AGL. I recall hours of GRM practice in a J-3 Cub preparing for the Commercial Airplane check-ride. Perhaps that's one reason I'm still alive after more than 50 years of flying.

The argument which says one should avoid low turns ignores the fact that every glider flight ends with at least one turn at or below 300' AGL. Unless a pilot is well trained for low turns this is a recipe for a stall/spin accident. I respectively suggest a better alternative is to find a CFI willing to provide GRM training in a touring motorglider or slow LSA and get really good at it.