In the end it takes the same amount of training to get there, but you can go straight through Cavern, Intro and Full Cave in one long 8 day course. In addition to their individual classroom portions, Cavern is 4 dives (2 days), Intro is 4 more dives (2 more days) and Full Cave is another 8 dives (4 days) - 16 dives and 8 really long days total.
Way back in the day the Cave course was 21 dives - usually over a period of a few weeks to a few months. The separate course approach is in comparison the "new" way to do it. This approach offers fewer total training dives but (usually) a diver picks up several dives between courses where the diver can gain experience and practice the skills learned at the previous level. From that perspective, you short change yourself from an experience perspective with the zero to hero approach, and if you do that, you'd want to be sure you dove very conservatively and not press the limits of the Full Cave cert until you acquired a lot more experience.
In the real world, it is common for divers to take Cavern and Intro, then take Full Cave a year or two later to gain experience in between. Alternatively, many divers also break in up even more by separating Full Cave into 4 dives and 2 days to get them to the Apprentice level and then 4 dives and 2 days to complete Full Cave up to a year later.
Another option if you have Cavern already is to take Intro and 2 days of the Full Cave course in one trip and then practice at the Apprentice level for a year before finishing Full Cave. Apprentice is a training level that expires, not a certification.
Way back in the day the Cave course was 21 dives - usually over a period of a few weeks to a few months. The separate course approach is in comparison the "new" way to do it. This approach offers fewer total training dives but (usually) a diver picks up several dives between courses where the diver can gain experience and practice the skills learned at the previous level. From that perspective, you short change yourself from an experience perspective with the zero to hero approach, and if you do that, you'd want to be sure you dove very conservatively and not press the limits of the Full Cave cert until you acquired a lot more experience.
In the real world, it is common for divers to take Cavern and Intro, then take Full Cave a year or two later to gain experience in between. Alternatively, many divers also break in up even more by separating Full Cave into 4 dives and 2 days to get them to the Apprentice level and then 4 dives and 2 days to complete Full Cave up to a year later.
Another option if you have Cavern already is to take Intro and 2 days of the Full Cave course in one trip and then practice at the Apprentice level for a year before finishing Full Cave. Apprentice is a training level that expires, not a certification.
