It just so happens I have my MOTU weapons training notes to hand - here is the section on the Lindholme (well it would have been if I could have posted the PDF document). However, I haven't got the applied notes with me, and I must admit I can't remember if we dropped so the dinghy was just downwind allowing the two containers to drift 'around' the survivor, or all upwind allowing the survivor to drift up to the dinghy. I suspect the former, cos the drift rate of the two containers was greater than the MS9.
I can certainly remember dropping them for training, or better still with the mail for lonely navy vessels (the first one full of old envelopes and bricks etc causing it to burst open on impact was always much more fun), but the only one I dropped for real didn't leave cleanly - either the nav didn't set the Connel Box correctly or there was a malfunction in one of the carriers.
I'll continue looking for the original procedure notes.
* * Pertama * *
PS On the Shack Lindholme the ropes (bouyant cord!)were 200ft and 400ft respectively.