I have like a 8*10 alongside my above ground pool.  12 years and has not heaved.  I used 4 posts 36" into the ground, filled with 30" stone and a concrete collar.  The stone pulls water away from the collar.  A little cross bracing and that thing isn't going any where no matter who dives off it 
  
I would use that post and anchor method if I was attaching another end to something stable, like your house.  I did do that with the large 2nd deck behind and attached to my house 
  
My pool side rails had like a 2 " bevel.  I brought my deck over the bevel so as to not have a gap between the deck and pool, leaving enough space for the cover