Hello,
The one transistor forward discharges the transformer magnetising flux by conduction in the auxiliary winding when the fet is off.
However, if N(aux) = N(pri), then the fet VDS goes to 2*vin during this flux discharge (transformer reset).
Not only that, but there will inevitably be leakage, and thus a RCD clamp will be needed across the primary, and this will mean even higher VDS voltage...as such, switch-on switching losses will be incredibly high.
Can we thus confirm that the 1 transistor forward is a seldom used academic postulation?