All I can think of that may have caused the lack of blooms last year is fertilization. The spring after I applied fertilizer is when there were no blooms. The fertilizer was specifically for azaleas, and organic; but perhaps it caused an adverse reaction anyway. Thinking this might be the case, I didn't fertilize after last spring. Maybe the restricted blooming this year is indication that the fertilizer was a problem, and recovery is in process.
And again I'm fascinated by how accurate a symbol this azalea seems to be for my extracurricular creative production over the past year: pretty, but sad and few.