Just on your point about the ex-dividend overhang, the same applies in reverse - i.e. if there are buyers en masse for the dividend, then that volume of demand should drive up the price prior to the ex-dividend date (presumably once the dividend is confirmed). So whether the stock is "cheap" after ex-dividend date requires a comparison with the current price.
The way I see it, a stock should never in theory be cheaper than its cash backing (unless that cash has been ear-marked for very quick expenditure, but that's not the case with EXS especially since it will continue to generate cash from WD and royalties that can help fund any future exploration). Therefore, whether you buy it now at 62c with cash backing of 62c, or after ex-dividend date at around 34c with cash backing of 34c doesn't make much difference - it can't get much cheaper than it is now. The only real difference is whether you can benefit from a franking credit or not.
EXS Price at posting:
62.5¢ Sentiment: Buy Disclosure: Held