Baldnessfalls, I just had 1500 at the hairline (I'm 8 weeks postop), and I successfully hid my procedure, so maybe I can give some tips.
As you've probably noticed from postop pictures, it will be obvious for a couple weeks following surgery that
something has happened at your hairline. There will be some scabbing evident (minimal if your doc gives you good postop care tips and you follow them studiously), and the skin will also be pretty red. And, of course, there will be those small, transplanted hairs. Personally, I wouldn't feel comfortable going to work after surgery with all of that exposed.
However, I purposefully grew my hair a bit long so I could sweep it across my forehead. I've never kept my hair close-cropped, so this wasn't much of a change from my normal style. It completely covered all of the work, so no one was the wiser. You should know, though, that there's a decent likelihood you'll have a swollen forehead pop up a few days after the procedure. Mine was pretty puffy, but I just covered by saying I had an allergic reaction to a topical ointment. The puffiness subsided in a few days.
You did ask about covering until you see a
final result, though, which I have to warn you is pretty impractical. I don't know what the degree of your loss is, but results aren't really final until about 12 months. Some shock loss is fairly common in the first 3 months (I've had very mild thinning in the forelock), and any native hairs that are shocked out will start to regrow after a few months. So really, you're waiting for a few things to happen: for native, shocked hairs to regrow, and for the transplanted follicles to emerge from the resting phase and grow. All of this
starts, at the earliest, at 3 months. Lots of folks don't see growth until 5 months, and that's only the
beginning of growth. It really takes 10-12 months for the shocked and transplanted follicles to grow in sufficiently to "fill in" the transplanted areas. I'd venture to guess that it'll be hard to keep a hat on for that entire time.
The upside is that if you're having 1500 grafts transplanted at the front, you're probably pretty similar to me--NW3-ish with at least a decent head of hair still intact. If you avoid drastic shock loss, friends/family probably won't even notice that your hair has changed--it's amazing how differently we see ourselves. There are plenty of stories about people who have had huge changes to their hair without their colleagues noticing. I covered the redness/scabbing with hair for the first few weeks, and now at 8 weeks I'm back to wearing my hair up and my hairline exposed. My closest friends and family are completely clueless that I had work done, even with some thinning at the forelock due to shock loss. You can check out my pictures at this thread:
http://www.baldtruthtalk.com/showthread.php?t=9370
No two people are alike, so even if you have a similar hairline, it's not guaranteed you'll respond identically. But it may be a useful comparison. Good luck, and keep us posted!