One of the most poorly kept secrets in the history of wargames in general and Warhammer in particular is Weapon Skill and how it determines the to-hit roll.
Short summary; higher weapon skill, you hit 66% of the time. Weapon skill lower by half on up to equal you hit 50% of the time. If the enemy weapon skill is double +1 higher than yours, you hit 33% of the time.
In other words, the best warriors hit precisely twice as often as the worst warriors (with exceptions granted for the extremely rare instances that can reduce to hit rolls to 2+ or increase them to 6+. They are so rare as to not warrant any further discussion here.)
Mush has been made of the new Tomb King ability to bump Skeleton WS by 4 points. Is this really a big boost?
From one standpoint yes. With wound charts guaranteeing any hit has a 17% chance to inflict a wound, doubling the number of times you successfully hit an opponent is going to increase your potential damage output exponentially.
And that word potential is THE key word here.
One key element that makes Warhammer work is statistical outliers. By this I do not mean when you cheat the dice and hit 5 times in 10 tries needing a 4+ (which is actually less than 50% likely to happen. There are 60,466,176 potential outcomes of rolling 10 dice; far less than 30, 233,083 of them will have 50% hit and 50% miss). What I am referring to is when you need a 5+ and hit that 7 times in 9 dice.
Of course, we are more likely to remember the failures. It is human nature. We can all remember times we needed 3+ to save and failed 4 of 5 (an event I can recount having happened to me numerous times) but we conveniently dismiss the times we have needed 5+ or better and saved 4 out of 5, even though those events have most likely happened a relatively even number of times. We tend to emphasize the spectacular failures in our minds and, when we remember the spectacular success, it is more rare in our memory.
Nevertheless, the reason weapon skill matters is potential. If we strictly went by probabilities Warhammer would be a very boring game. However, because we have times when 10 With Elves sweep in against 20 Night Goblins and somehow only get 2 wounds through while the Night Goblins somehow hit 8 times and see all of those wound, we continue to have an interesting game.
When it comes to weapon skill, we are more likely to have those spectacular successes where 14 out of 15 attacks hit if we start with a higher than normal Weapon Skill.
I know that is a basic, basic assertion but it may not have reached some of the more luck-reliant players in Warhammer.
If your weapon skill is say..5, you are going to need a 3+ to hit most of the time. If your weapon skill is a 3, you are going to typically need a 4+ to hit and if your weapon skill is 1, you typically need a 5 to hit. Again, basic assertion, but there are more potential rolls that include 10 of 10 dice showing a 3 or higher on each one than combinations that show 5 or higher.
Thus, there are more potential opportunities to inflict a wound with a higher weapon skill.
Which brings us back to the percentages discussed earlier. How important is it to select troops with a higher weapon skill?
I typically use the Warriors of Chaos book as it is the one with which I am most familiar. In that book, a common debate is which is better; trolls or ogres? I myself never take either; I like the dragon ogres. And I do that specifically because of the weapon skill being one pip higher.
Ironically, I cannot think of a single time that made my Dragon Ogres more difficult to hit. They are typically hit on a 4+ by line troops and a 3+ by elites. However, it often means they are HITTING on a 3+ instead of on a 4+. The extra 16% chance to hit...well, okay, more like 10% when you factor in the times it has no effect...is worth the extra points to me (plus they just look so much cooler).
From a mathematical standpoint, this is a mistake. The extra points in a typical unit would provide me with an additional 25 great weapon wielding marauders. In other words, making the selection is a points waste...from a strictly mathematical point of view.
However, with the role I designate the Dragon Ogres for, it is worthwhile for the POTENTIAL it gives them. They are more frequently going to hit that low WS monster with a majority of their attacks.
Which brings us back around to the original question; how important is weapon skill? It depends on what the role of that model is. If your model has a high probability of dealing damage when it connects with an attack then weapon skill is actually very important. Being 16-1/2 or 33% more likely to hit and give yourself a chance to wound is a huge deal.
Conversely, if a model is designed for roles other than close combat, then a higher weapon skill is at best of marginal value. If your skirmishing peashooters of destruction melt when hit in the face in close combat in the desert by a snowball then a higher weapon skill is far less useful than...say...higher movement or better playing skill to keep them from getting into that combat in the first place.
High weapon skill is nice, and it can be broken down by percentages. How valuable a high weapon skill is is directly proportional to how likely a model is to do damage when in combat....and how likely it is to live long enough to swing.
But it is not the most important stat.
Plague Marine Squad #6 & friends completed - Finished my last Plague Marines today meaning that all 41 inc. 5 Dark Imperium sets and 2 lots of the easy-fit Marines are now all painted. Just leaves me...
5 days ago