Various extension services and other info-resources support the notion of winter time draw-downs for managing aquatic vegetation, but I suspect that this tactic is only marginally successful on a limited number of aquatic nuisance weed species; and mostly only on exotic aquatic species that originated from warmer climates - such as water hyacinth.
In short, the winter draw-down tactic "might" help reduce weed biomass - temporarily - especially in northern climates, but probably has very limited impact on established seed-banks.
It is feasible to "gradually" stem the growth and/or control both sago pondweed and coontail with fluridone, assuming the site-conditions are suitable for this chemistry. Although this option doesn't eliminate the possibilities of DO-issues, it might be better (safer) than allowing the weed-growth to continue unabated.

Kelly Duffie
Cypress, TX