I will take a contrary view (how unlike me!), and say that I think it is not such a bad thing - the problem is it is inconsistent in it's application, therefore any SA gain made for the ATC is diminished.
When it came in, last year, it was used a lot more - it seems to have drifted out of use now.
My own view is that it was a band-aid fix to the amount of wake turbulence 'encounters' that ATC were manufacturing - partly as a result of the introduction of FNC's (Flight Number Callsigns). We all used to know that -OGB, RMD, EAA etc were all heavies, and CZU, TJA, TAF etc, were mediums.
QFA1122 doesn't mean much until you look at the radar track / other track. (We dont look at strips much these days - rarely in approach). Herein lies the problem - the H and the M in the TAAATS font (especially in MAESTRO font) look almost the same - and I, fortunately, have excellent eyesight - consider the average age of an approach controller is mid to late 40's, and the vision implications of that, and you can see why it regularly gets missed. Not to the point of an 'encounter', but becomes a surprise nonetheless.
There has been an effort to change the colours of the Wake Turb indicator - unfortunately this seemed to make it worse.
Anyhow - just some background. You only have to say it on first contact - we dont think you are wankers - it's saving us haveing a short 'holiday', so my personal view is that it's not a bad thing.
[Below is a picture I discovered on the web, which indicates the Wake Turb indication - normally labels are green or blue]
