To me this sounds like a bad idea all around.
I definitely disagree that crafting is 'sewn up'. I've seen quite a few new crafters popping up - and for Armorsmith and Weaponsmith in particular, there have been a ton of great recent spawns that are available, or that you can at least get your hands on just asking the community. New crafters may not have every server best resource - but that is mostly unnecessary except to appeal to the people that think 10-20 extra protection or 4-5 damage matters - which in all honesty - it doesn't. It's unrealistic to expect every new crafter to be able to produce capped everything and to make a huge change like this because they can't.
If it were the case that crafting was 'sewn up' and new crafters were unable to tap into the market - I don 't think the solution would be to introduce a tool that would cause Armorsmiths and Weaponsmiths produce less armor and weapons thereby sinking less server best resources. If people are needing to buy less armor and weapons, I would think THAT is what negatively impacts new crafters trying to break into the market.
Also - anyone that says decay is brutal is a hardcore PvP'er (they make the world go 'round) or dies unnecessarily in PvE, and are too cheap to insure their gear. A set of RIS with repair capability can last 6+ months - and I can bet some people could push much longer than that.
...and there is a big difference in a set of armor costing 7 million credits and a crafter 'making 7 million a suit'.
Ultimately - I've got a ton to gain from this tool being implemented, but I think it hurts more than it would help.