Nay it is not time wasted but it is not the best timing for legumes, unless you are in an area commonly plagues with dormancy of say alfalfa.
The majority of what soys and sanfoin are dining on now is P and K etc from your past mgmt over the last 5 yrs. Legumes prefer high residual fertility but will also use some nutrients applied in-seaon. N and S will see plant uptake wihtin 6-8 weeks, some of the K will be taken up until the roots must dive deep for soil moisture/nutrient feeding, unfortunately most of the P is for next season.
This is one reason we prefer heavy fall applications and like to split soil samples, say 0-4" and 4-8". We want the nutrients down early and well entered into the soil cycles before peak crop growth and hopefully enough fall/winter rain for them to migrate down the profile. When 0-4" becomes dry and unable to feed a summer crop, then we want to know what the deeper reserves look like...sufficient or not?
I have some June 2 planted beans and July/Aug are normally droughty. Beans should be first trifoliate or better by this weekend with good prior soil fertility applied. It will be an opportunity to take a bag spreader and do some repliated AMS+muriate apps just to see if we can improve crop health/growth. The experts say I don't need S and K, but some of my testing and observations say otherwise. If we get more rain we will know if it works, if not then it is food for the soil and next crop!