You can be in the best shape of your season and still be behind on the time you said you'd run. Fitness is a measure of you. Ready is a measure of you against a race.
What a form score tells you
A score built from your load and your own best form answers a useful question: how well are you training compared with your best? It is a fair read of your block. It says nothing about a half-distance on 5 hours 30 or a 10K in 45 minutes.
What a race score tells you
With a goal time set, the better question is: if you raced today, how far from the goal would you finish? Take the projected finish, transitions included, and compare it to the goal. At or under the goal is 100. Every one percent slower takes five points off. That is a number about your race, and it moves as you train.
Where the time is likely to come from
Slicing the gap equally across swim, bike and run feels fair and is wrong, because each leg's goal is derived from your own projection, so every leg looks the same percentage off. A better split is by headroom: the legs where your form sits furthest below your own best have the most to give. That is where to spend the next four weeks.
Illness and injury belong in the score
A readiness number that ignores the flu you had on Tuesday is flattering you. Rate how rough it is, from 1 to 10, and the score should drop with it, more if it lasts, and more again if the injury is in the sport being scored. After recovery the drag should fade over the days it takes, not vanish overnight.