I think there are some sub-species of Muledeer But they are usually seprated by something more then a state line, I was born and raised in South Dakota, We get both Whitey and Muley that break the magic mark of 300 lbs a few each year make it to that weight, Cornfed deer do put the weight on jus like beef cows.We too have some bucks that aren't very big( Bodywise) but have a great set of horns,Kind of like runts of the litter thing, But the really big bodied ones make the racks look small(have missed judged more nice ones that way) Yes I use to cut meat for a living, I have weighted in alot of deer, So yes I have seen the log books, You have alot of things that will turn a so-so year into a great one for weight and horns, Nice wet late spring, thundershowers in the summer great feed for all the horn and body growing season and a early snowfall to move those big ones out of those deep dark hiding places, Then you see the weight and age jump up. Take the big snow storm (UTAH)a couple of years back man the weight jumped up alot because a lot of older class bucks was taken then the following year it dropped back down again not as much snow not as many Big bucks pushed down to be taken, If you look at SE Utah I do believe the 5 day seasons are having a good turn-around in that area, I have seen better bucks in that unit because of the short season, Are they getting bigger I think so, I know age class is starting to creep up and that is a good sign for 5- 10 years down the road. You Can over SHOOT a area and killing to many of the Big Bucks does a harm to the overall herds you bet. If you have 500 great Bucks and you have 300 taken in a snow year, you just left a bunch of does that will be breed by smaller bucks as long as those bucks are of the same gene pool as the bigger bucks your good, But if they are of a 2x3 buck that isn't in a good genetics class type buck, you have just witness the start of the downfall of that herd because as more of those "Good tpye bucks are killed the more those bad genetics creep in. It's kind of like you don't let a shetland pony stud breed your $10,000 dollar quarter mare and hope for a top roper. That is what is happening in some area's they need some new genetics brung back in to off-set the damage that has already happen. But that my opinion Heck I could be wrong, But that's the way I see it.