Don't forget though the role of a wicket-keeper changed dramatically in our generation, in the past you'd seldom see a keeper doubling up as a world class batsman.
The role has not changed. They still can wear gloves and pads on the field, and they can still bat. Perhaps you mean the expectations of batting ability and run scoring of keepers has risen post Stewart, Flower, Sanga, and the one who incorrectly gets all the credit, Mr Adam Gilchrist. It has reached the exalted and contentious heights of AB De Villiers, the best batsman in the team, the world even , keeping wicket (and averaging 58). But thats not really different to Andy Flower keeping.
The point is that batting from a wicket keeper was always important. That is why Alec Stewart kept wicket ahead of the more able gloveman Jack Russel. Its why Wayne Phillips started keeping for Australia, albeit with his batting failing in the weak Australian side era post Rod Marsh. Les Ames averaged over 40 in the 1930's as a test wicket keeper. So batsman like run scoring from a keeper is not as novel as you may think if you are part of the "Gilchrist changed it" mentality.
Dhoni isn't very flash as a test keeper, bangs a lot of runs at home but is fodder anywhere else. Horrible captain. I'd rate McCullum ahead of him.
Dhoni captained India to a world cup win and #1 ranking in tests. I will concede that he has had some amazing batting talent and quality spinners n his arsenal, but only an ageing Zaheer and a whole heap of crap for seam up. Maybe his 38 average in test cricket compares to Brendon's 34. But MSD has definitely kept to more spinners than Brendon, and his 294 dismissals is comparable to McCullum. McCullum only got through 54 tests or so as a keeper, Dhoni managed to get through over 90, and lot more limited overs matches. I think MSD's ODI batting record is misinterpreted favourably by the masses. But to rate McCullum ahead of Dhoni is contentious at best.
You should not criticise Dhoni's batting record comparatively without taking a close look at McCullums. McCullum has played near half his career as a specialist batsman. The facts are, he only scores runs on Asian roads and bullying Asian teams touring New Zealand.
http://stats.espncricinfo.com/ci/engine/player/37737.html?class=1;template=results;type=batting
BMac has plundered a double century on an Indian road (match where Habhijan Singh got a century) and scored that double century against Pakistan in the Philip Hughes test in the UAE. That skews his touring record against India and Pakistan as being excellent.
His away record anywhere else that is not Zimbabwe or Bangladesh is sub 30. He has plundered Blangladesh and India at home. His record against Pakistan at home is weak. And so is his overall record against Sri Lanka notwithstanding his double against them last year.
Basically, he scores runs on Asian roads that do not turn (because if they do turn as in Sri Lanka, he then fails), or when Asian countries that are not Pakistan tour New Zealand with pathetic seam bowlers. And Zimbabwe.
He is dominated by Australia, England, South Africa, West Indies, and typically by Pakistan when not on a UAE road where Philip Hughes has just died. Even Sri Lanka, bar that 195 on Boxing day typically have the best of him in New Zealand, let alone his 22 average in Sri Lanka.
Fact is: McCullum's 2014 is well after he quit being a keeper and inflates his current batting record but consisted of plundering a weak Indian seam attack on a road for a triple ton and double. Philip Hughes dies leading to a strange test match on an UAE road where NZ and Pakistan play 3 spinners each and Rahat Ali (36 bwl avg) and Mo Talha (56) opens the bowling for Pakistan and he scores a double. Pakistan went from 4-311 to all out for 351 and Craig got 7 wickets in the first innings. For me, that is the 'Phil Hughes' test. And he got a slogging 195 against a Sri Lanka team with no quality seamers on a Christchurch road.
So if you havn't got the gist of it yet, here it is. McCullum's record as a combined batsman sole and keeper batsman is no better than Dhoni's record as a Kepper batsman. Dhoni likes playing in NZ too. Averages over 50 here in NZ. But if Bangladesh, India and recently Sri Lanka continue to tour NZ with no decent seamers, BMac will get runs. But noone in England, South Africa, Pakistan, Australia or the West Indies teams will come to the New Zealand concerned about BMac's wicket on past performances, and that includes his century to set a total to chase of 106 against Australia in a match lost by 10 wickets. Because he cannot play good seam bowling, and we won't give a touring India or Sri Lanka a turning pitch to play on when they tour.
Prior, not even a comparison.
Prior averages 40 as a keeper. McCullum 34. McCullum debuted in 2004. Even on a Gilchrist changed everything analysis, that is well into the Flower, Gilchirst, Sanga period. Flower debut'd in 1992 and his test career was over in 2002. Gilchrist was about to have his batting fall away in 2005 Ashes and have his average continue to decrease.
So while I may disagree with you on the whole generation thing changing, the fact is, you concede that it had changed before McCullum debuted.
If Bmac does not score big runs in the test series against Australia, in the future when assessing his batting as against BJ Watling or international keepers, I think many cricket fans will refer to BMac's batting prowess as a keeper batsman (or in general) as 'mythical' in that lovely Antipodean expression "he's a myth". But if he scores big against Australia in February 2016, and New Zealand win the series in a 1-0 or 2-0, he will be incredibly fondly remembered in his almost certain soon to be announced retirement.
