on the fast bowling debate:
did they really play less cricket in yesteryear? english (or foreigners in the english county game) played a ridiculous amount of cricket, with a real county treadmill of game after game - often a three day game might be interrupted by a one-day game on the other side of the country. in season they might get a day off a week.
what they played was less "high intensity" international cricket, particularly limited overs. they might have bowled more overs, but Holding for example was not necessarily bowling as fast for Lanacashire in 1981 as he was bowling this over to Geoff Boycott in a test match
what the bowlers did was actually more match bowling, with less training and gym sessions etc. i'm no sports scientist and this may be utter bullshit but my hunch is bowling is a very unnatural movement, and no other training prepares you to bowl as well as bowling itself does. by doing more match bowling the bowlers were able to retain rhythm and bowl faster when they needed to.
regarding ABdeV:
it's ludicrous to compare across eras for the "best ever" for a few reasons:
1) the laws of the game (whether LBW, amateur players, uncovered pictures, fielders on the leg side, number of bouncers per over, number of balls per over, existence of limited overs cricket, field restrictions in limited overs, power plays in limited overs) have changed so much throughout time as to make any comparison of players - even statistics based ones like strike rates - meaningless.
2) who and where people play and the comparative strength of the side they're in and their opponents vary
3) conditions: pitches, bat size and technology etc. have changed massively and things are more in favour of the batsman now in limited overs than they have ever been. it's no surprise that even a few years ago scores of plus 300 and individuals plus 100 were seen as very good performances - now the measure is more 350 for the team and 150 for the individual - nobody had ever scored a double hundred in ODI's 4 years ago now 5 people have
4) the Bradman problem - even though i think statistics shouldn't really be compared across generations even if you do this cricket has an outlier in Bradman further ahead of everyone else than anyone is or has ever been in any other sport. you simply cannot look past him for best ever
also, notwithstanding the caveats i've said about comparing across generations and comparing stats across generations in particular, i'd say ABdeV isn't even the best batsman South Africa have ever produced... Not that he actually got to play for South Africa but that distinction belongs to Basil D'Oliveira: look at what he did in the "coloured" leagues; look what he did when he played in the few first class games he got a chance to play before coming to England; look at what he did coming to England at an age most people retire nowadays... he was an unbelievable player.
ABdeV is one of the best players around at the moment (i think there are several players at the absolute top with precious little if anything to separate them)... i think that's compliment enough because there are plenty of great players around