We already know The Gun Guys have mental problems, but beyond the known problems there is even more.  Which do you think it is?  Do they have reading comprehension problems? Arithmetic problems? Or maybe both? Here's the evidence, you decide, from an email I received today:

But the most important of these is definitely the "one handgun every three months" law.  Currently, anyone legally able to buy one gun can legally buy any number of them-- illegal gun dealers know this, and therefore use it to buy weapons in bulk, which they then sell to criminals.  This law cuts that right out, and doesn't come close to bothering "law-abiding gun owners,"  Who legitimately needs to buy 36 new guns every year?  A similar law is being worked on in Pennsylvania right now, which would actually limit the purchase of handguns to one every month.  And if you really need to buy more than 12 handguns per year, you should get another hobby.

If he didn't understand one "handgun every three months" meant something different than "three handguns every month" it was a reading comprehension problem.  If he mixed up multiplication and division then it is a serious arithmetic deficiency.  I'm giving him the benefit of the doubt and assuming he knows better than to believe there are 58 months in a year but with all the mental problems he has the possibility exists he could be living in some sort of imaginary alternate universe.

If you are ever asked why limiting your purchase rate is a bad idea here are some answers:

• Registration:  In order to enforce laws such as these registration of all (hand)gun sales with automated retrieval of the data is required.  If you don't understand what is wrong with that then you have more reading to do (also here and Molon Labe). 
• Legitimacy:  The constitution (Federal and most states) protect the right to keep and bear arms.  Where did they acquire the authority to ignore the constitution?  And if they claim "reasonable regulation" such as "shouting fire in a crowded theater" comparing it to the First Amendment you answer that if they are allowed the power to restrict you to one gun a month then they also have the power to restrict it to one per year, one per lifetime, or ownership of only one gun at a time.  A better comparison would being only allowed one letter to your congress critter each year, or one blog posting per week.
• Effectiveness: It's already illegal for convicted felons to own firearms.  A law prohibiting you and I from buying more than one gun every N units of time will not matter to them.  Such a law would not be any more effective than the current laws against the manufacture, sale, purchase, and use of some recreational drugs.

And the best answer is, "It's a bad idea because no one has yet answered Just One Question."