I have watched "Mastering the art of pickpocketing" (I think its called) with James Coats in it and it shows how to remove watches. I didn't notice this type of watch.

It is hard to explain for me so I have taken pictures of it.

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This is the watch fully open from a side view:

http://i91.photobucket.com/albums/k281/ ... 010046.jpg
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This is the watch fully open from the back view:

http://i91.photobucket.com/albums/k281/ ... 010047.jpg
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This is the watch semi open from the back view (the right strap in the picture folds and closes first):

http://i91.photobucket.com/albums/k281/ ... 010048.jpg
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This is the watch closed from a side:

http://i91.photobucket.com/albums/k281/ ... 010049.jpg
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This is the watch closed from the back:

http://i91.photobucket.com/albums/k281/ ... 010050.jpg
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It may look simple to undo but it is impossible to undo it with one hand, if I try to use two hands the person will definitly notice something strange as it is a strain to undo even with two hands.

Does anyone have any tips or suggestions on how to undo a watch like that.. and take it off?

It is explained on Mastering the Art of Watch Stealing. If you don't want that, check out Chappy Brazil.