Romances was Luis Miguel's third album of classic boleros and love songs from the rich history of twentieth-century Latin music. As Rod Stewart would find a decade later, it was almost impossible not to keep indulging his audience's nostalgic streak; the records sold too well.
Even the fact that "Por Debajo de la Mesa" (underneath the table) isn't a classic, but a new song written by Miguel's long-time producer for the Romance series (Armando Manzanero, himself a classic song composer of the 60s, 70s and 80s) speaks to the exhaustion that's begun to set in, not only with the series, but with Miguel's own pop career. Only twenty-seven at the time of release, he's already accomplished more than he could have dreamed; and the kids are coming up from behind. Miguel's standard of four hits a year has been slipping for a while, and will only slip away in the years to come. You can build quite a nice career on nostalgia, as thousands of aging entertainers have found; but at least in the modern world, you can't be a pop star too.
"Por Debajo de la Mesa" is a love song — underneath the table he caresses her knee, and then spends the rest of the song wondering what will happen next. Will she accept his advances, will she awaken the fire in his blood? He can't live without her, etc. It's a professional song, professionally arranged, but while Miguel sings it with all the tenderness at his command, he can't make it into a timeless work of beauty. It's filler — gorgeous filler, but filler. And the kids are coming up from behind.