I'm not an expert or a support person, and I do understand your frustration with the official responses in this thread. If the only answer is going to be "we're working on it but have no specific timetable" for well over 6 months now, why even bother responding?
Or "24-48 hours" sync time -- that is not sync, that is, well, something else "not sync".
Having said that, I experience delays only when I am using an external internet calendar (such as Tripit). My desktop Outlook calendars (one Outlook.com and one an Exchange server) sync correctly and swiftly between my Surface, Outlook on my desktop, Outlook.com,
Modern UI calendar, and Windows Phone 8 calendars. As does email. In fact, it is the best sync experience I have ever had in over 15 years of trying to sync calendars and email across devices. At least as good as I had with Google and Android, and better than
I've had with Mac and iPhone.
Staying entirely within one "ecosystem" seems to help a bunch. Ironically, the most prolific cross-device app these days seems to be SkyDrive, Outlook, and Office. Still, I use a mixture of Amazon, iThings, MacThings and Microsoft cloud apps. Devices are
MacBook Air for laptop, Surface for tablet, iPod for music, HTC 8x Win Phone 8. I had to give up on Google when they started shutting out my Windows phone and Outlook sync. I have a Droid in my drawer, but I'll be darned if I'm going to switch phones or go
backward just to be able to use Gmail, etc.
Seems like what you want to do should be working unless you are relying on an internet Calendar. Good luck.