" The way I see this is you [Croumagnon] have
asked a question [should I sell GTCB and buy ZGEN] that can't be answered by any serious person"
I disagree. Each of us who has held onto GTCB and not bought ZGEN has answered the question. The answer -- by inaction -- may not be an informed one or a well-considered one, but it is an answer. The decision to hold is not fundamentally different than the decision to buy.
That's not to say that in the real world, anyone -- particularly the majority of us who have other jobs -- can really act as if every day were a new buy or sell decision. But I don't think it is a bad idea to occasionally ask yourself, if I did not own the stock already, would I buy it, or would I buy something else that is more attractive.
Speaking for myself, as my firm has some involvement with a client that owns some ZGEN, I can't buy ZGEN without going through a difficult approval process. So it is easy for me to evade this particular question.
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