Ex-Scotland and Lions captain Colin Deans was part of the Northampton coaching staff just before 22-year-old Tonks arrived, but has continued to follow the club’s fortunes,
Deans said: “Greig will be a real bonus for Edinburgh. He has been in and out of the Northampton squad, but any time I have seen him he has impressed.
“Greig is one of those guys who, when you see him, you think, ‘Why hasn’t he been getting more regular games?’ and then you remember [England international] Ben Foden is at the same club and it becomes more understandable.
“After probably being at the wrong club at the wrong time with Foden around I suspect all he needs is regular game time.
“What Edinburgh are getting is a good lad with a confident air, a well-built ball carrier who has a massive boot – bigger even than Hugo Southwell.
“Tonks can also run like the wind. I’m confident he’ll blossom in an Edinburgh side with his natural tendency to run the ball very positively.
“Utility value means he can play in any of the back three positions as well as centre or stand off. There are some class players in Edinburgh’s back line, but he won’t look out of place.
“I really expect Greig to flourish under the coaching of Michael Bradley, who I played against when he was starting his international career with Ireland and I was finishing mine.
“Bradley has struck me as a first-class operator, a real gem of a coach who Scotland would do well to move up into their coaching structure in some capacity.
“This really is another example of Bradley doing well in the transfer market, too, because the South African prop who is due over soon, WP Nel, is highly rated also.”
On the subject of Scottish coaching, Deans says: “Not renewing the contract of defence coach Graham Steadman is strange because defence hasn’t been so much of an issue as poor scrummaging and Massimo Cuttita is still there.
“Also, I’ve been disappointed with some of the selections to the point where I question myself and ask if I’m missing something.
“For example, why did it take until last Sunday to get Duncan Weir in the Scotland team when Ruaridh Jackson isn’t yet the finished article?
“I found myself frustrated for spells last season when Edinburgh were struggling for stand-offs and Glasgow had both Weir and Jackson on their books.
“With the SRU contracting all home based players surely one of them could have been transferred across to be developed. Surely Andy Robinson could have made that happen?
“Having said that, Greig Laidlaw ought to have been taken to the World Cup to cover stand-off or scrum half and recognising that Scotland played well against France I’d still make changes for the visit to face an Ireland side who could struggle through playing three games in just over two weeks because of the Paris rearrangement.
“By the time you build in recovery time there is not a lot of opportunity left for them to prepare for the visit of Scotland who should start planning now for the next World Cup because this Six Nations has gone.”
An ex-hooker, Deans said of his successor: “Against France I was really impressed by Ross Ford who after 55 caps did what he should be doing – Ross really lead by example.
“But as I’ve said before, I can see Ross doing what [World Cup winning captain] John Smit has done for South Africa and play either prop or hooker.
“That would open up a place for Pat McArthur of Glasgow who I really rate as a prospect with the unfortunate Fergus Thomson hardly able to get on the pitch through injury.”
That would be the scenario for Deans at least until his current work in progress helping convert former Scotland under-21 captain Neil Cochrane from flanker to hooker is complete.
Deans revealed: “Neil has joined Bedford near where I live and I’ve been asked to assist him in his switch to the front row.
“I still think he is young enough at 28 to fulfil his ambition of representative honours given the commitment he is showing to get up to Premiership standard in England and maybe then back to Scotland.”