[drcy]

The rule is you disclose information and let the buyers decide. One collector may not care, one may care, one may it think the date of the cut doesn't matter, one may think it does matter-- and personal sentiments are a perfectly valid reason for determining a buy price. There are a lot of personal taste, personal aesthetics reasons for a valuation.

P.s., if there's nothing wrong with it and it shouldn't effect value, then there should be no problem in disclosing it. The reason people don't disclose things is because they believe the disclosure will lower sales price.

Disclose, disclose, disclose. It's not up to the seller to decide which value-effecting material information the buyer should receive, in particular as it relates to how an item has been physically altered decades after it was made. The seller doesn't get to "rationalize away" all the information the seller "doesn't need," especially when (by pure unforseen coincidence, of course) that disclosure would lower the sell price.

And if you think there's nothing wrong with a 1933 card sheet cut in 2015, great. If you want to specialized in modern cut cards because you consider them just as valid, go for it. That's a perfectly valid personal collecting sentiment. And if you think a 2015 reprint is just as pretty and is just as valid to you as a 1933 original, that's perfectly fine personal judgment-- but that doesn't excuse you from disclosing that a card you're selling is a reprint.

In short, if you think modern sheet cut vintage cards should be worth the same as vintage cut cards, that's fine. If you think modern sheet cut vintage cards should be worth the same as vintage cut cards so you don't have disclose to potential buyers that a card was modern cut, that's not fine.