Why would anyone bother paying extra markup for a mining amp when they can just use a slider?
You don't get it, right?
I'll try to be as pedagogic as I can (I know I'm not that good of explaning, but I'll make a try).
First, mining amps adds a multiplication factor to your deposits.
If you use a "x2" amp, then when you've found a 5 ped raw deposit, you're getting a 10 ped deposit to dig. When you've found a 10 ped raw deposit, you're getting a 20 ped deposit to dig.
If you use a "x5" amp, then when you've found a 5 ped raw deposit, you're getting a 25 ped deposit to dig.
That's how amps work (right?).
Ok, now the example of my "sensitivity switch" (as you call "slider"):
If you set it to High Sensitivity, as an example, you get following deposits:
0-2-1-1-1-0-0-0-0-4 -> You use 10 drops, you get 10 ped back.
If you set it to Low Sensitivity you get:
0-0-0-0-0-0-0-0-10-0 -> You use 10 drops you get 10 ped back.
Let's say you support your mining by sweating. You can only afford 5 bombs.
With High Sensitivity, you get 5 ped back.
With Low Sensitivity you get 0 ped back. Or you're lucky and get 10 ped back.
You're a professional miner. You have thousands of PEDs to spend.
a) You just want to spend some time, maybe want to tiergrind finder or to gain skills. Or you want to mine in a new area: You use finder in High Sentitive mode.
b) You're a gambler. You want to use big amps and go for ATHs on asteroid: You use finder in Low Sensitivity Mode.
As for using residues to increase return in mining: If you can't tell the difference between a crafting machine and a finder you should get better glasses.
If you're still saying "It's going to ruin the amp market", then I just say "sigh". Gamblers can still use amps if they want and they would work as Before with sensitivity switch set the chosen way.
If you say "Only gamblers should be allowed to mine - any other way and mining amps will be out of work" then I say, as far as we know the mining amps Always have just add a multiplier. Either the cost of mining amps is justified or not. Either it's an advantage to mine "fast" or it isn't.