Players always take pay cuts

Any time i start anew game i look at the wage structure of the club to see who are overpaid etc. What i always find is that if you offer a player less wages with no signing on fee they accept, you can seriously reduce your wage bill this way.

Eg. Player X starts on 100k per week with key player status,

i offer 90k with no signing on fee, he accept,

i then offer 80k, he accepts, and so on.

Ive once got a player down from 88k to 24k. it's been the same of every series of the game so far, has anyone else exploited this?

It's a known - as you say - exploit. Unrealistic unless you're managing Clyde.