I had a technical level bust after a windshear go around a few years back. ATC didn't actually see it but I knew I had done it so ASRed it. Even one level bust can hugely skew the statistics for a small airline and the regulator starts getting very interested. Fortunately on this occaision a bit of 'liason' between the company and ATC revealed that we were only at 3300' for one sweep of the radar and the ATC manager decided that given the weather conditions (which caused the GA) he didn't regard it as a genuine level bust. The ASR was subsequently 'redrafted'.
My lesson; ATC are your friends...