'go long on any index and hold'
Well that isn't a very good suggestion - my husband held on to his FTSE100 shares for about 8 years and didnt even make break-even when he sold them recently. I think you need to qualify that with 'and keep a close eye on the markets'.
although Ross wasn't very clear, it's not as stupid as it may seem. The FTSE100 "index" consists of the top 100 shares within any 1/4 year, it gets reevaluated every 1/4, hence holding onto a specific "stock" is not the same as holding onto the "index", as the index constituents is changing. Simple such strategy that Ross might be eluding to is:
1. Determine ("best guess"!) current market trend, bull/bear
2. (Assuming "bull" as example) Buy index at some pullback
3. Set stop at say -3% (or previous low), trail daily stop using some favourite method etc..
Rather simple, won't make a huge profit, but will make a profit!