It might interfere with your testing and after your software has crashed a couple of times, your application might start to no longer behave erratically.
As JohnFrum wrote:
“I learned about this feature a few weeks ago while debugging my service. It had been crashing and then it seemed fixed and I couldn't repro it again. Moved it to another box and it started crashing again. Finally I noticed a line in the debugger that I knew wasn't mine about FTH and thought ‘WTH? Ahh, nice!’ I like it but I'll turn it off on my test systems.”
The Fault Tolerant Heap page has the details about disabling it. For more information about this, check the video at Silviu Calinoiu: Inside Windows 7 - Fault Tolerant Heap
À demain si on le veut bien.