We show that heating of harmonically trapped ions by periodic delta kicks is dramatically enhanced at isolated values of the Lamb-Dicke parameter. At these values, quasienergy eigenstates localized on island structures undergo avoided crossings with extended web-states.PACS numbers: 05.60.Gg,05.45.Mt,42.50.Vk,82.20.Xr Controlling the state and the time evolution of quantum systems is one of the central themes of current research in experimental and theoretical atomic physics, quantum optics, and mesoscopics. Tailoring wave packets in Rydberg systems [1], producing single photons on demand [2], creating coherent superpositions of macroscopic persistent-current states [3], and, most recently, the controlled production of multiparticle entanglement [4], are prominent examples of what is often coined as "quantum state engineering", such as to stress the almost perfect control we have achieved on matter on the microscopic level. Whilst many of these schemes still rely on an analysis of the quantum dynamics in terms of some unperturbed basis of the quantum system under control, it has become clear during the last decade that generic features of strongly coupled ("complex") quantum systems allow for novel and often extremely robust strategies of quantum control. In such systems, studied in much detail in the area of quantum chaos, peculiar eigenstates emerge which exhibit unexpected (and unexpectedly robust) localization properties and dynamics. Most prominent examples thereof are nondispersive wave packets in periodically driven quantum systems [5], quantum resonances [6], and quantum accelerator modes [7]. A considerable part of these "strong coupling" quantum control schemes relies on some underlying classical dynamics, which in general is mixed regularchaotic, and precisely the rich structure of a mixed classical phase space is at their very origin [8,9]. A large class of these systems follows the Kolmogorov-Arnold-Moser (KAM) scenario [10], i.e. regular phase space structures are destroyed gradually as the coupling strength is increased. Yet, there is another kind of classically chaotic dynamics, which goes under the name "non-KAM" chaos [11], where the phase space flow is fundamentally altered at arbitrarily weak perturbations. Recently, the consequences of such non-KAM transitions have been observed in electron transport in superlattices [12], where enhanced transport accross the lattice was observed, due to the sudden (non-KAM) appearence and disappearence of unbounded stochastic web-structures in classical phase space, at well-defined values of some control parameter. Hence, enhanced transport was enforced by (controlled) abrupt changes in the underlying classical phase space structure.