is it now that plugs have a 60k or maybe 100k miles lifespan and the age they are in situ, that makes them challenging to remove do you think ? everything seizes-up !
In olden times when plugs were changed every 12k miles or at each main service, and when a set of plugs cost about £2/10/6d, that it was an easy job to do .
Just reflecting a little I'm afraid
Malc
maybe there's something to be said for just loosening and pushing back home, the plug leads, every year or so