User blog comment:RoznosicielCiast/Least popular champions/@comment-4996845-20130125032054

The problems of Heimerdinger and Trundle are of the same origin. Thing is that in meta that is shifted very heavily towards mobility and positioning the good old troll has little to no way to do what he does best: get in the enemy carry's face... and stay there for good. With no hard CC, no mobility apart from his area where he gets a MS boost, and no burst to talk about, his only function remains a borderline counterpick - although admittedly, he's one of the select few champs that are capable, if not likely, to come up on top against 2 very common and strong top lane picks, namely Wukong and Jax. Therefore while remaining viable, Trundle is not likely to see more use as of s3 unless reworked.

Pretty much the same goes for Heimer. In the new meta, i mostly see three kinds of apcs - mobile assassins, one-shot aoe bursters and tanky sustain casters. Unfortunately for heimer, he is neither, lacking all of mobility, burst and toughness. And while a rework is underway (it has been leaked that he's to be made into a sort of beefy, area-controlling sustained AP bruiser), as of now the only way for him to be of any use is a heavy area control team (something along the lines of J4 top, Amu jungle and Leo support) which would know not to fight grand teamfights, preferring extended skirmishes, in which case heimer's insane poke with rockets and huge sustained turret damage would become significant. Either that, or you'd need a splitpush-centered team, avoiding teamfights altogether and leaving heimer to do what he does best - keep the enemy at bay underneath his tower.