What specific advantages do tubeless tires truly offer for cross-country racing, and are these benefits significant enough to outweigh the added complexity, potential for tire damage, and increased maintenance requirements, particularly when compared to high-quality, lightweight tube-type tires in terms of rolling resistance, traction, and overall performance, considering that many professional cross-country racers still opt for traditional tubed tires despite the claimed benefits of tubeless systems, and how do the results of recent studies and field tests support or contradict these claims, given the often-contradictory anecdotal evidence from amateur and professional riders alike?