My uncle likes to use the UK as a base for travelling to Europe. I'm not entirely sure why, as even though I and my cousin (his son) live in the UK, he still stays in a hotel. While we do the occasional UK driving trip, he could easily consolidate the UK portions and mainland Europe portions.
This spring/summer he flew from Australia to London and has already gone in and out of the Schengen Area twice, with plans for another 3 trips, so in total he will go through UK immigration 6 times and Schengen passport control 10 times, plus endure train rides to and from LGW, LTN and STN.
He hasn't had any problems with immigration the past few years he has done this.
Wow, your uncle really likes a punishing itinerary !