Glad you're back Griff & feeling better mate
mw1954 I know what you are going through atm. I & I'm sure most went through it when 1st trying to get pull offs to sound half decent.I recommend looking at the DVD of Griff explaining it - ofcourse I'm assuming you have BGU - it may be on one of his extra's too , not sure someone will answer that.The thing with a pull off is not to just lift the finger directly up from the string it more of a flicking action downward - hard to explain i know - & that gives it the extra ring.Justin Sandercoe even calls them flick offs.
Like everything else it will develop over time & practice.
I am still working on mine as after 20 odd yrs of not playing it doesn't come back to you after a week or so been at it now for 8 months & getting there - should be pretty dangerous i reckon in about 5 yrs time !
LP