As for goalies in any sport flexibility can be an important tool to stopping the ball. And to reach your hight of flexibility you need to stretch BUT it is VERY important that you do it correctly and at the right age etc. Brad Appelton's page has LOTS of info on strecthing, don't let the bulk deter you, take you time and find what you need.. There are also several books about stretching so of to the library to find what you need, a book I can recommend is "The Art of Goaltending" by Vladislav Tretiak that covers so beginners stretching, mobility drills, reflex drills etc. a book for icehockey goalies really but it has some good stuff in it.