If the canopy comes open on a Legacy on early takeoff, it will pop up really high and blank off the air to the horizontal stabilizer and give you real pitch issues.  If you are not going too fast at the time it will bounce up and down and your pitch control will come and go.  Makes for a real mess cleaning up the upholstery after you get stopped!  :>)  Don’t ask me how I came to know this information!  :>)

Bill B