SP directly affects how much can be uploaded at one time, but I'm not sure why that would be of any real concern during the PoC stages.
STEEM already has a lot of bloat and what I am doing, anyone can do. It is easy to politely ask me to be careful, but if someone wanted to attack STEEM it wouldn't be so easy to ask them to quit.
I have a decent amount invested in STEEM and powered up on my account. I would personally like to see STEEM do well.
If a 5MB upload can make the entire network freak out and hit a bug that prevents lower level users from doing anything, the network wasn't QA'd under heavy load. My experience is of a QA manager. And I can document exactly what was done when I triggered any issues, reducing time to find a fix by a considerable amount.
Trust me that I'm not going to intentionally break things. But also remember that anyone anywhere can do all of this with