I'm not so sure the tactics were all that great at Rourke's Drift. Not that what happened there wasn't a great feat of arms. But they were using a .45 (heavy) round against guys armed with spears (taking into consideration the suppressing fire from Zulu Warriors with weapons from the column). It really wasn't all that even a matchup.
The Brits just had to keep the volume of fire up and keep the "fort" intact. I understand it is not as easy to do as it sounds but their job was easier than that of the Zulus. For the Zulus, they had to cross some 100 yards of open ground, clamber up on top of fortifications, climb down and then get at the British. The whole time, they are being shot at and, at the end, they face several British soliders with bayoneted rifles that have the reach on them.
There really wasn't much the British did from start to finish but hold ground. That, is something the Brits are famous for doing very well. Historically, and as a group, the Brits are very hard to get out of a place once they get there.