Lower sharpening angle = thinner edge = higher mechancial advantage to the edge = "feels sharper" ... and it would, indeed, cut more efficiently than an 'equally dulled' double bevel (simply because of the edge's higher MA) ... but it should be 'truly sharp' before you use it on game.
MOST (not all) of the single-bevel BH's on the market have much harder steel in them than MOST of the double-bevel BH's, because it takes a harder steel to hold the thinner single-bevel edge during penetration. That higher quality, harder steel also means they will retain their sharpness far better than most double bevel BH's (though there is at least one double bevel with excellent, high quality steel; the Silver Flame).
Ed