I don't think you have to be a strong swimmer. But I'll tell you, from my experiences over the last year as a DM, that you need to be STRONG and have a LOT of stamina to be a good DM, at least the kind that works with classes. You will haul an enormous amount of equipment, and you will do a lot of walking and standing with your own gear on. I told Peter after this last class that I knew what the swim test were for -- they weren't for swimming. They were just for plain old garden-variety stamina, because you need a lot of that.
Hear, hear! Also, the times I need a DM the most are when everything is going pear-shaped, either logistically or during the diving. I've been around some DMs who are great when everything is going well, but they have so little stamina (or perhaps fortitude) that when things get wonky and I need them badly, they're ready to call it a day. The DMs I rely upon and consider worthy of the title are the ones who, when the fins hit the foam, can reach into their reserves and get the job done.
On the trip I just got back from, we were towing one of our divers out over the sand to the edge of the reef slope on most dives in order to save her air for the diving (as her air consumption was high and she was stressed about it). No big deal. Add herding catfish for an hour's night drift to that, coupled with a rougher-than-expected exit complete with surf, large ankle-twister rocks, and plenty of fire coral to weave through, plus a good ledge to step up, and you're to the point where you really want your leaders to be able to reach down and grab some spare strength and stamina to get everyone out safely and relatively easily. Our divers had a great time, and although we slept very well that night (after some conversation about how rough and not-fun-for-us the dive was), we had it to give when we needed it.
Of course, when it comes to stamina, there's nothing intrinsically special about being able to swim half a kilometer in a certain amount of time, but it would hardly be logical to add in cycling, running, and stair-climbing alternatives to a scuba course. :biggrin:
I'm just getting ready to start my DM training...I had knee surgery a few months back and am only just now getting back into real shape. I've never been a swimmer (I prefer being underneath the water on scuba rather than on top of the water with or without a snorkel)...it should be interesting. I guess I'll train for the test rather than just show up and hope to do well.
lacycroft, please, I implore you, look at the simple, easy, one-page
ZERO to 1650 in Six Weeks by Ruth Kazez. If you follow it (three swims a week), by the fifth week or so, you should have your swims licked. I've never yet had someone who stuck with it fail to complete our NAUI 450yd/10min swim (or the easier 900yd/18min snorkel), so I'm quite confident that it can help you. I've found it immensely more beneficial than just trying to get better, as I've had several people give up and wash out who seemed to be putting in much more effort but without any framework.
(Incidentally, if you *do* use it, please let me know how you find it and how it works out for you. I'm always interested in hearing other people's experience with it, as personally I only have so many DMCs worth of data to go by.)