I have designed par 5 openers enough that a few locals who have played many of my courses wonder if that is one of my design standards. It is not, but if that is the way the land falls, that is which way I go. From memory, I count only 7 of about 40 regulation courses, and another 2 because they flipped the nines.
When I do it, I strive for a true 3 shot par 5 for most players, just as I avoid short and drivable par 4 starters. In both cases, either waiting for the green to clear so you can reach it, and/or still being within 3 Wood range after a muffed shot or two, causing minor delays as some players must wait to hit their second (or third) shots can get everyone's round off to a slow start.
In theory, par 5's give enough length to get golf groups away from the clubhouse, and are technically easier than par 4 holes, although hitting a 3 wood off the turf on the second shot of the day does cause some consternation among many.
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