Just another thought I wanted to add, but to your question beachgal, there is a decent chance in July that your weather will be calm enough to do the same as we did, or as you suggested, tow the dinghy behind you while you snorkel (although I would never recommend actually tying the dinghy painter to your body) and holding on to the dinghy like that would necessitate a significant amount of additional caution. Among other reasons, you would need to be careful to keep the dinghy far enough from the reef to not damage the coral. There can also be currents around Eustacia that can be unpredictable.
I'm not sure of the legality, but there were sandy areas close enough to the reef where I think one could reasonably use the spare anchor from the boat to anchor the dinghy in a sandy spot a reasonable distance from the reef so as to not cause damage to the reef and still be close enough to swim to the reef and back. If considering this approach, I would recommend only doing so with a high level of expertise and swimming skill/strength for both personal safety and safety of the reef. I briefly considered doing the same with our dinghy anchor, but didn't trust it to hold even in those calm conditions, and didn't want to take any risk of damaging anything or getting us into trouble with anyone.
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