You may well be right, but the serious mistreatment amounted to it being exterior woodwork exposed to UV and foul weather. Of course, you could say I should've revarnished it more regularly, but then my 'ease of application' bit kicks in.
This may well be it, although it doesn't seem to stain per se, perhaps because I used the very pale light oak. However, the Ronseal does the job required which is to weatherproof the exterior woodwork with a nice aesthetic finish. Worked nicely on the internal woodwork around my rear slide too.
This sums up perfectly the direction I've taken. I'm not sure about varnish looking 'much' better, but if an expert was doing my woodwork for me for a similar outlay, I'd happily let them use it! They could even use the Le Tonkinoise I bought for the job before I realised I'd rather use the additional time to be out boating!