I'm in the 'yes' camp as well.

I was about 30 when I started travelling a lot, and although it cost me a bit more to go WT+, then its only 4 return trips to get silver (assuming you are not Euro based). Thats actually not bad, especially if,as you say, you tend to book at the last minute or during peak seasons when WT is only a bit cheaper. Whats 'sold' me all that time ago is that 'cheap' WT+ is still cheaper than full fare Y but earns 15 TP's more. And when silver you get better treatment if things go wrong. If you are likely to do ~10 long-hauls a year then statistically this might well feature in your near future!

Sorry for the ramble... wine talking