Yoshihiro was interviewed by French Site Metagames.fr heres a excerpt from that interview which has been translated by PSP Vault
How did you come to the PSP? Do you own other consoles?
I came to the PSP because I found it was not a bad device at the begining and when I got my hands on one, homebrews weren't working yet.
A this time I used my PSP to watch my pictures but also to test its weakness and study its behaviour during the launch of eboot.pbp files like the 1.0 update from Sony launched in January 2005.
For the other consoles I own a modified PS2 with a HDD, 2 Xbox (one modified with a dev kit) and a modified Gamecube.
Ive mirrored the entire interview via the comments so that full comments can be made.