I think it is almost always good choice to make a HU deal, if you think at the moment you don't have much edge over your opponent. And it reduces variance a lot. Also headsup icm and chip chop deals are same. I don't actually know what kind of deals pokerstars or other sites offer, haven't done much deals, but if there are 3 or more players left u should be more careful especially if there are two deal options
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