I started in 2011, and on a net basis, I didn't sell any ounce.
Net basis = I sold some various kinds as to limit the variety of the stack, but used (nearly immediately) the fiat to buy more of the kinds I limited to. So just like SilverPete.
About the "buy and hold at all costs" mentality, my thought is this: try to avoid paying too much in the 1st place. Buy when silvers market appears dirty doom and dead, and hold, wherever higher the price goes later (the latter is more a working-together anti Parasites strategy of myself so consider it an option not a rule).
For those that failed to avoid, there is a market wisdom out there: a succesful speculator sniffes out small losses while they are still small. Put in other words: sell first.
For those that failed to sell first (or soon enough), there is another wisdom: one that the WooHoo Bull/Bear price instability fanclub hates: hold stubbornly. This fits in aboves anti Parasites strategy, since it makes their buy back in more expensive / shrinks the fluctuations. What the silver market needs is a much more stable price trend. Stability generates confidence, and chews out money from competing markets, it makes the market bigger after you bought and more demand for your chunk.
Btw: in the end, we'll ALWAYS sell the stack, so your questions answer changes with time, and price (

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