Let's take an example:
If $FTM pumps in price, it won't 'outrun' $SCARAB.
The APR will vary in terms of its $USD value, but emissions won’t. This is something that wouldn't be possible with another 1:1 pegged asset like a stable coin LP position, where the $USD value is directly tied to the emissions. If $FTM rises in $USD value, $SCARAB goes with it. Same if $FTM falls in $USD value, $SCARAB will be worth less in $USD, but it won’t affect the peg. The only thing that can change the price of $SCARAB in terms of its $FTM value is buying and selling it.