Technically, they should all allow you to take all of your leave. The 'hassle' part of it is a different issue. If you're in a department where you're fortunate enough to have a partner, then you can generally take leave whenever you want and your partner can cover (assuming he's not a dick). This would include Neurosurgery. The truth is that most military neurosurgeons spend most of their time doing spine, not intracranial cases, so the acuity isn't the same as it might be at some larger volume centers. You probably won't find a solo partner who is willing to accommodate extended periods of leave (because you're dumping call on him alone until you return). The biggest issues in a situation wherein you have a partner is that patients back up. How much they back up depends upon how busy you are. When one of my partners takes leave, our schedules generally fill up across the board for a period of time proportional to how long that partner is gone, and it takes a few weeks to catch back up (and we're booked out 4 weeks at baseline). If you're a solo provider (and I've been there too), it can be a huge, huge deal to take leave. Again, very technically the command can't stop you. They can "direct" you to take leave at times that are more convenient for the hospital, but let's face it when you're the only guy there is never a more convenient time. So good commands will realize this. Bad commands will throw a fit every single time you request leave. Especially for surgeons, you have to rearrange your surgical schedule sometimes for weeks ahead of time (can't do, say tonsillectomies within 2-3 weeks of leave because one might come back bleeding). Your patient log will get ridiculously backed up unless you have someone (say your NCO) start kicking everything out to the network while you're gone but if you have a bad command climate this will come back to bite you when they try to punitively make you see more clinic because you're "losing too much" to the network. these situations can be amplified or mediated by the presence of a nearby civilian specialist in your field who might be willing to cover your patients while you're gone. Generally, he will want reciprocation while he's out of town, and whether you can do that and whether or not the Army totally alienates that civilian provider is entirely up to your command. So yes you get to take your leave. And you should. But the Army can - possibly - make it such a huge ordeal that you won't feel like doing it.
