Actually, this is something I still wonder. It’s been a while since I played it (2009 or 2010-ish) but my memories of the game are a bit different to my friend’s who played it in 2012.
I had a pirated copy (I’ll buy it one day to make up for 11year old Taka’s mistakes!) and it started off normally. Nothing was unlocked… but I had free reign to enter any route I wanted to enter. I followed the in-game decision tree (something my friend said didn’t exist) to gather up all the little Tiger stamp things, and then finished the ending of HF.
I’m not sure if it was a special patch or something, but I’d like to find it again for when I get a copy of the VN. The anime will hopefully hype me up enough~
I can’t think of a single multi-route VN I’ve read that didn’t have at least one sub-par route~