Well that depends on your definition of "reasonable". If by "pinching open the blade" you mean one handed, then no. If you mean opening the blade without using the nail pull, then yes. I can do it that way and I am by no means a phone book (can I still use that term?) tearing animal. It can be done but it's much easier to just use the nail pull. Of course if one has tiny little nails prone to breakage (as some women do), I would suggest finding an easier opening knife.
Thanks for asking
Guy