Rationale behind pass-through slot height

What was the rationale behind the limited height of the pass-through slot? Was it just a safety issue, as Dan suggested, or were there other technical obstacles that required that limitation?

From the “Hey Tony” thread.

The most glaring reason from my research is the safety concern. And I might add there may well be a design reason as well. The focusing distance is very small and since a CO2 laser can only really cut 1/4 inch I am assuming that was where the limits were set.
I like you, am a consumer and cannot speak for the company but I have been here since the start of the presale and have seen this question pop up over and over again so this is my response from the collection of answers I have read over the last few weeks.
I am sure that the company does not want to promote this, but there is the option of overriding the limit switches for the front drop down door that will allow for feeding thicker items in the front. As far as the back door, though you will have to use your imagination there. A Class IV laser is not something you want to be lax about. Especially so in a product that is actually designed for in home use.