In which case Terry wasn't a transfer from Chelsea you mug, he was a free agent.
But again my bad for not realising you're too stupid to understand context. I'll try to make things more at your level in future.
You didn't say money transfers duckie.
Doing things at my level would involve asking the question you actually want answered and then reading the actual answers given, rather than inventing ones that fit your world view.
But it's all baby steps.
How about DeAndre Yedlin, £5m from Spurs to Newcastle two summers ago? He's a 24 year old American so don't try telling me he was a Spurs youth player. They signed him from America
Alex Pritchard went from Spurs to Norwich, having come to spurs from West ham
Richie De Last went from Leicester (the champions) to Villa.
Tiago Illori went to Reading from Liverpool, having signed for them from Sporting. Reading also signed Tyler Blackett that same summer from Man Utd
That was all 2016-17.
Charlton signed Christian Cellebos from Spurs, who had got him from Barcelona and Watford signed Gomes from Spurs, who was in his early-mid 30's then.
Is that enough for you to fuck off with your little tail between your legs or shall I go back further?
Can I specifically find a precedent for a player that Arsenal specifically bought, specifically for £17m, specifically going to a lower championship club?
Not within the last three years, which is all the research I'm going to expend on this argument.
Does that mean we cannot possibly have enquired, which is all sniffer ever said?
No it doesn't.
Every one of those transfers happened because something was wrong with the player- a young player not up to it, an older player no longer hacking it or a signing that didn't work out. Perez will leave Arsenal for exactly the same reason and whoever has the money will do the talking.
I seem to remember Robinho moving to Man City which was pretty much an equivalent shock and drop in status for him