Few neutrals would agree with the Lilywhites boss after City and Preston exchanged blows throughout a breathless contest which saw the League One encounter swing both ways in the final three minutes.
Leon Clarke and Callum Wilson cancelled out goals from Tom Clarke and Bailey Wright for North End before Wilson put the Sky Blues ahead in the 83rd minute.
But Coventry, playing their second home game of a gorundshare at Sixfields, were pegged back when Joel Byrom levelled matters at 3-3, before Chris Humphrey and then Mathieu Manset struck for either side in injury time.
Grayson's Preston have now drawn all four league games this season and he was less than impressed with the entertaining draw.
He said: "It was probably great for the neutrals and for the supporters but, from my point of view, it was a shocking game of football.
"Yes, we scored four goals but that's as poorly as we have played defensively, with and without the ball.
"Over the course of the game we probably didn't deserve anything but when you score four and go into the lead with a minute to go, you think you would at least show some desire to hang on to it.
"The last goal probably epitomises the game. We didn't go with runners, we didn't stop the cross and let somebody free in the box. It was a disappointing performance all round.
"The goals we scored just paper over the cracks of a poor performance. From start to finish it disappointed me. We knew what they would be like and that we had to match them but we didn't.
"We were too open. We've looked hard to beat early in the season and here we looked like we could have conceded half-a-dozen."