Well, I do agree that you shouldn't use root ferts when you add substrate. It's better to use root ferts to 'spot fertilize' where you plant your plants.
However, nearly every plant can take in nutrients from both the substrate and the water column. some plants, like swords are HEAVY root feeders, and should have root tabs put under then when planted, and new tabs added every 1-2 months (depending on what type of tabs you have).
If you can't get aquatic plant root tabs, and have to use Jobes, make CERTAIN you use the jobe's for Lush Palms and Ferns...and that you break each stick into 3-4 pieces, an use 1 piece per plant, and bury them deeply.