I'm not sure why people don't just clean and leave it.
Its a working part that gets clogged up. It only needs a clean probably every 20-30k. I recently did it on my dad's 160k BMW three series diesel. It kept getting errors and I didn't even need a code reader.
I simply drove it (he has had it chipped) and noticed a load of black smoke blowing out the back.
I simply said clean the EGR and I bet it'll be a load better.
Did it. No smoke loads more power.
Its routine on diesels with these valves.
Not sure why you'd blank it to be honest. Its helps with fuel economy.
Alfa 166 2.0 Twinnie - LPG and a few trick performance parts