Tom D.,
I would rather our first meeting be over dinner as opposed to having you see a gimmick par-2 or 3 of our creation!
My belief that there were likely very short holes in early golf (ancient golf) has to do with the implements and balls then in use. While "cross-country" in nature, the game was more about accuracy in hitting a target (and hole) and less about distance. If anything, the records speak to the lure of people hitting small balls to small holes with small clubs. Small holes, then, would be in order. Several factors are at play in this hunch: Balls would ge lost over longer distances, hitting many shots would be tiresome, etc. Of course, there is also the idea of the single long hole (12,000 yards), but this is unlikely to have been all that much fun as mathematically the match would have been won long before one player holed out — the losers being well behind and not able to verify their opponent's score or even be in the vicinity of the finish line.
Holes were easy to construct in ancient times. After all, they were nothing more than a literal hole dug into the soil. The more of these "easy" holes present and you would, in essence, have the potential for shorter distances between them. And, in the end, shorter shots from one hole to the next — at least in theory.
The reason for building a short hole (today) would need to be land-driven, or a severe need for such an interruption in a round. Had we three par-3s in a row, one of tremendous short length may be called for. The par-2 concept we are looking at is driven by constriained land due to some very ill planning on the part of now-long-gone land theives (planners). It also provides variation among a round with five par-3s otherwise.
I disagree slightly with the notion that approaches to par-4s are identical to the shot value of the very short par-3. At the tee one is presented with a unique set of circumstances: (i) bystanders and the nearby "audience factor" with multiple sets of eyes trained on your every move, (ii) the thought and prospect of the uncommon hole-in-one, (iii) honors, (iv) a set place from which to strike the ball that is not the doing of the golfer, and (v) the freshness of walking up to the tee to be presented with a new picture of a problem to be solved — not the longer walk from your previous shot to the next, as is the case at the longer, par-4 or par-5 hole.
By the way, the word "gimmick" stems from a gambling device which is used to artifically control winning at casinos — not all that bad a concept. I liken the word to "Bandaid", a term often used to describe a temporary fix to a problem. But, when one considers of the true meaning of "Bandaid" it is not at all a bad device or term. In reality, a Bandaid does exactly what it is supposed to accomplish, and without them our world (and my 8-year-old daughter) would be worse off. "Gimmick" is not all that bad either, for our world needs them in order to break up streaks, otherwise boring lulls, etc.