I don't really understand the logic in that.
There are plenty of people who use Merch Informer making 4 figures a week doing their own research and employing a designer.
This my experience. However I may be wrong. There is no harm in trying except if you are not designer then the cost of designs. You can always try merch informer trial to find keywords.
I don't want to discourage people for trying Merch by Amazon but Let me dispels some of the myth according to me.
merch by amazon is
1. Not a done once and forget it method. If anyone is thinking that once they upload certain designs and wait for monthly check then they are absolutely wrong.
2. It is not that easy to find keywords from merch informer and make design, upload and wait for money to roll. There are thousands of people stuck on tier 25. Even my one of the JV account stuck at tier 25 since one week.
3. If you are not careful with Trademark/copyright then your account will be closed in no time.
If you are determined to go for Merch by Amazon then here are my some suggestions.
1. Don't over depend on any software, instead Study and understand Amazon search engine. Most people know that when you type a word on amazon search, you will get some suggestions like google search engine. This suggestions are most important. It is based on what people are searching. Evolve your own method to find low competition keywords.
2. Take concept from highest selling tee (no need to invent wheel) and create design ( Never ever copy)
3. Be prepare to spend money on design if you are not designer. You don't want award winning design. So, No need to spend fortune on designer. Check best seller you will find lots of design with simple quote and common font.
4. Learn how to design only t shirt in graphic software like photoshop, Gimp etc. No need to master graphic software.
5. Always evaluate your account weekly. Your gross income - tax - cost of design. Percentage of selling like you uploaded 20 designs and selling only 2 designs then it is 10%. This percentage will varies as you upload more designs. Keep a sharp eye on it and take immediate action.
All the best.