Ballet has been with us at least since the 1500s. Modern dance closes out its first century over the next 10 years. Now take aerial dance: A very small handful of pioneers got interested after Terry Sendgraff presented her first experiments with something called a single-point trapeze in 1976. Even so, another decade and a half would pass before modern choreographers began widely exploring extended movement off ground, when a host of companies (including Lisa Giobbi’s Movement Theater, Frequent Flyers and Project Bandaloop) took to the skies between 1988 and 1992.

All of which makes aerial movement in modern dance, by various reckonings, an art form somewhere between 17 and 29 years old–the age range of most students attending this year’s American Dance Festival.

The problem? It shows.

Can it be any accident that the most accomplished work we’ve seen in the field comes from artists like Cirque du Soleil’s Igor Arefiev and Colette Morrow, who’ve extended a significant background in circus and trapeze work, or Giobbi, whose physical disability forced her to pursue dance off the ground a decade ago?

For the rest, aerial dance has seemingly been an incremental acquisition at best–one which North Carolina audiences already know more than a little of firsthand.

Those already impressed with Karola Luttringhaus’ fearless and furious spatial choreography in the 1990s, both at North Carolina School of the Arts and with Winston-Salem’s alban elved dance company, were forced to ratchet down their expectations when the group decided to go airborne at the dawn of this decade.

Particularly in their first years, alban elved’s aerial choreography lacked much of the eloquence, finesse, velocity–and strangely enough, the daring–of their ground-based work. Though a much higher standard was clearly present in their conventional sequences, the company opted for growing up in public, staging their own gradual acquisition of technology and technique in incremental works that, in retrospect, were not uniformly ready for public consumption.

As here, we found, so elsewhere–in the works of Project Bandaloop and Pilobolus’ Alison Chase, for example. Much of aerial work–and many of its workers–still seemed preoccupied with acquiring and mastering primary techniques. Few performers appeared as comfortable off-balance and off-ground as they were on. As a result, though aerial dance’s initial impulses involved radically expanding and liberating movement from the horizontal plane, its vocabulary of movement (and range of expression) remained quite limited when compared with land-based choreography.

Which is what made Brenda Angiel’s 15-minute work South, wall and after a particular revelation when the world first saw it at the end of an evening-long ADF showcase in 1998. Angiel’s dancers turned the back wall of Page Auditorium into a floor across which they walked, ran, jumped, scrambled and played with ease. Just as suddenly, our vantage point in the audience of Page Auditorium had been shifted 90 degrees, as we seemed to peer down from a vertiginous second-story ceiling on activities below. No aerial choreographer to that point had taken our perceptions of the world and so literally upended them.

If we expected similar quantum leaps after that, we were destined to disappointment. The following year, audiences learned over the course of Angiel’s first full evening at ADF that her featured previous work, 1997’s Otras Partes, while strong in places, was not as uniformly developed as what we’d seen in 1998. We wrote off the difficulties in her work in the International Choreographers Commissioning Program here in 2002 to the lack of experience her ADF students had–forgetting that South, wall and after itself had been created with three ADF students and three company members back in 1998.

Ironically, Ms. Angiel’s first bid for the future, the world premiere of Air-lines, seemed a bit of retro indulgence–a tribute to the stylized animation and color palettes that graced the opening credits to a number of films in the 1960s. What first appeared to be five spotlights on a quintet of dancers splayed flat against the back wall of Page Auditorium turned into separate digital color field projections that morphed and moved with the dancers.

And moved they did, to Juan Pablo Arcangeli and Martin Ghersa’s percussive score. After initial patterns segued from a giant letter “W” to a series of ambiguous characters on something like an ever-shifting eye chart, Air-lines’ mobile rebus suggested a synchronized Olympic competition for geckos–or possibly chameleons, given the changing colors of their individual pools of light. Arms, legs, and bent and straightened torsos continually pushed and redefined the boundaries of the illuminated zones that video artist Mariano Iglesias created for each dancer.

But the first section of Air part plateaued early in an over-long exploration of the different ways a soloist, Leonardo Haedo, might be partially or completely supported, lifted or dropped at times by a cable attached to his right hand. Nor would this be the only section of the evening that seemed more devoted to exploring a question of technique more than an aesthetic or artistic one. At first, Natacha Visconti and Haedo’s subsequent duet seemed locked into considerations of tech, with both dancers connected to aerial cables by their left legs. Moments of play ultimately came out, before both dancers again became preoccupied with kludgy moments in technique toward the end.

The sense of playfulness only fully emerged in the last movement of the work as Ana Armas, Viviana Finkelstein and Cristina Tziouras jumped around, leapfrogged and otherwise lightly walked all over Haedo, Pablo Carrizo and Abel Navarro, a trio of men in white.

After intermission, the world premiere of Air force provided similarly mixed results, truly achieving ignition only in Armas and Carrizo’s final tango-based duet. Aerial magic enabled Armas’ impossibly long leg extensions, letting her lightly slide down Carrizo’s leg at one point, before walking up his torso and out across his arm. Individual moments still seemed a struggle with technology, before a compelling finale in which each dancer scissor-legs the other ever closer, culminating in a passionate embrace–a moment of full, robust characterization, commitment and choreography, particularly when contrasted with so many of the intellectual “what-if” exercises that preceded it.

The reiteration of South, wall and after that closed the evening seemed anticlimactic by comparison. A sagging near-lethargy haunted moments in the work, which experienced difficulties in the unison sections as Angiel’s quintet pendulumed back and forth across the back wall. This iteration lacked much of the freshness that its initial showing had.

Apparently, even the greats in this field are still assembling its language and its aesthetic, moment by moment, gesture by gesture. Though the evening had a number of individual passages that amazed, these too frequently were stitched together with considerably plainer fabric.

What does this genre need–besides another 10 to 20 years’ work on primary techniques and aesthetics?

I have one possible answer: dancers of similarly long development. When I looked back at Angiel’s earlier programs, I noticed that only one dancer from the company that visited ADF in 1999 is still with her troupe. Three of the present company of seven have only been with her since 2003.

Could the repeated need to retrain new dancers, presumably from scratch, have contributed to the very incremental progress we saw from Angiel this year at ADF? Or is this merely the speed at which this art form grows with the support it currently can find?