I was a slow runner just running for fitness. Back 15 years ago when I had just started running my one mile time was 7 minutes 30 Seconds running in my old trai

I was a slow runner just running for fitness. Back 15 years ago when I had just started running my one mile time was 7 minutes 30 Seconds running in my old trainers that I had lying around. I then bought a pair of 'mundane' running shoes (Mizunu Waverider 9s) and literally overnight my one mile time dropped to 7 minutes. Thirty seconds just gone after upgrading my shoes. Where do you draw the line at how much tech is too much tech?