It's important to realize that a) there can be anatomic reasons for these problems, which is why an exam is warranted, and b) not all docs have any idea what's involved in diving. A physician who recommends Sudafed must be sure that there ISN'T an anatomic problem, and should carefully brief the issues involved in the use of the medication, including heightened anxiety, increased susceptibility to arrhythmias in those with a history, and lowered seizure threshold, which is an issue for people with any seizure history, or using Nitrox. The patient should also be counseled about the issues which may occur if the drug wears off underwater, or is insufficient to relieve the problem. Difficulties with descent are one thing -- the worst that happens to you is that you lose a dive. Blocks on ASCENT are entirely other -- you have no choice but to go to the surface, and if you cannot equalize on ascent, the best outcome you can hope for is a blown eardrum. The worst is permanent vertigo and hearing loss, which can be really debilitating.
Confession: I have used Sudafed (and Afrin) for the purposes of diving. I am very careful about how I do it, use it only to relieve MILD symptoms, and I do NOT push my ears at all if I am using the drugs. And I know I've taken a risk of permanent, major injury.