Originally posted by Tinker:
I like that simple mechanic for performance tinkering - but how do you stop the powergamers keeping on and on until they get 150% ?
Besides the fact that they don't know the rule exists, you mean?
Firstly, the time involved - each attempt may take a couple of hours or maybe a couple of months, depending what is being modified and how much difference it makes to the game.
Secondly, the cost/availability - maybe the tweak needs a part that can only be obtained from a world that has just entered a civil war. Something that uprates a M2 Drive to M3 will cost almost as much as an upgrade, and may require the ship to be dry docked for months. Where will they get that sort of money? They'll need to embark on a number of hazardous adventures to finance the operation.
Thirdly, each time a mod is attempted, the ship will have to be trialled to test its performance - more time and cost - and risk. Jury-rigged mods can break down at the most inopportune times, and remember, performance reduction cancels the Annual Maintenance Get Out Of Misjump Free Card. And they won't know performance has been reduced until they try it out...
Fourthly, all mods have to be carried out on-table, haggling for parts, blackmarketeering, theft from naval stores, etc. Parts that significantly enhance performance are going to be proportionally harder to locate or manufacture.
Fifthly, mods can easily be reset to standard performance by standard technicians during Annual Maintenance, even going as far as
"Oh, is that what it did? Sorry mate, I thought it was just a temporary repair so I replaced it with an original part - all the scrap went to the recycler yesterday!"
If all else fails - the GM may be a mild-mannered geek by day, but 'you wouldn't want to see me when I'm angry'. There isn't a powergamer alive who is more powerful than a powerGM.