According to the original factsheet the investment strategy is to allocate
50 % to PP,
30 % to Rolex, Breguet, AP, VC, Cartier,
10 % to "exceptional contemporary watches" and
10 % in cash
I don't know how that strategy has played out but bear in mind that even though the fund might invest in much less PP's (pieces) than for instance Rolex the value of the PP-stock may still be along the intended strategy. After all you could get 10 exceptional Rolex for the price of 1 exceptional PP.