Many old slabs contain not only undergraded coins, but errors too. I recently purchased 3 old slabbed silver dollars with unattributed, very strong clashes. Here's one of them.
Nice. You got me looking through my slabbed Morgan's. Love the old ANA holders. Nice color and conservatively graded in my opinion.
Those clashes between the arrowheads and the eagle's left wing are not that rare, and the "cap vee" seen between the wreath and the eagle on the right is probably one of the most common. Unless there is a letter transfer, you won't even find them mentioned in the diagnostics. Most VAM's aren't even attributed by NGC & PCGS. Chris