SMITHSON (SSON) – Investment Trusts Price: £16.33 +6.9%NAV: £16.81Market Cap: £1.87bnYield: 0.4% Smithson, the closed-end fund focused on capital growth by investing in high-quality small and medium-sized companies, sprung a major surprise on the market this morning by announcing it would switch to an open-ended structure. The reason for the move is to eliminate the ‘entrenched’ discount to NAV (net asset value) which has dogged the fund almost since inception. The new fund will continue to be run by Fundsmith, with Simon Barnard as portfolio manager, there is no dilution or capital gains charge for shareholders who want to roll…