You are very correct Marc Anthony, the G4's are usually a good indication that the buck will score well. On the other hand, it usually needs another characteristic feature as well to push it into the 140" rang, such as; heavy mass, long G1's, exceptional spread or long main beams. If it has one of the before mentioned and good length on the G4's it will usually score well into the 140's. My 10 point this year had great G4's, good mass, decent spread at 17 3/4" and really good mains at almost 26" each. What he did lack was G1's although he did have about 2" on each side, if he would have had more he would have scored enough into 150" to keep him there with deductions. But again, you are correct that the G4's are a good way to make a quick judgment when it comes down to it unless another feature is more prominent such as the case with some of the 140"+ 8 points I have seen and harvested.
All in all, it takes alot of field time and study of pics to get a good feel on field scoring a buck. Lord knows, I have had my share of good ole ground shrinkage. Where I finally made a break through is realizing, through my own misjudgment, to subtract about 15" from what my estimation was at the time. Another words, if I thought a buck would score 140" at first, I would bank on a solid 125" buck. I'm sure I have underestimated some bucks but at this point in my hunting life I would rather do that than it to be the other side of the coin.
I have also been studying for a long time to be more proficient in field judging the age of a buck. Some older bucks may not carry the best set of antlers in the woods. A 4 1/2+ yr. old buck is a trophy in itself regardless of his antler score. You get one up on a buck of that age and you have just scored on one of the wisest animals in the world, in my book.
GREAT buck by the way Marc!
Thanks! Your bucks look awesome also! Nice job.