Holman had excellent technique for that era. Releasing the ball during the slide facilitated accuracy--- a must in that era. Today's game places much more emphasis on creating power and area through late timing and dynamic wrist action. On sport shots today, there is still a premium on accuracy but there is a bigger premium on hand action. That was a no-no in the old days due to the conditions and equipment of the earlier era. I do believe that some of the best players of today would have done well back in the "day", and some, perhaps even better. But I would venture an educated guess that they would not be lofting gutter caps or banking the gutter, with wide open shoulders to boot. Some posters have pointed to a few old videos of players in the 1950s shooting big numbers playing up the 10 board. That did happen, but not very often. In those days we had to contend with burned out heads, high boards, low boards, lanes dressed with hand held oil guns. More often than not, if you wanted to score, you had to keep your angles strictly in front of you--- no leaking to the right of target, no matter how many revs you might have had. And you had to throw the ball SLOW on those conditions or your rubber ball would deflect off those solid pins like silly putty (pins were not top heavy like the double voided pins of today).  Anybody who claims that they averaged 200+ in those days fell into one of 2 categories: 1. They were either the BEST bowlers in their region or, 2. They were bowling on blocked conditions (illegal at that time, not like the standard THS today).

Let's try to give credit to the best bowlers of each of these eras. The very best developed physical games that BEST fit the conditions and equipment of their time.
That includes the likes of Marshall Holman and Belmo. 

I seldom get my "heckels up" but on this subject, I must, because I bowled in both of these eras. Those who claim that bowling back in the old days was easier simply do not know what they are talking about and those who demean the incredible talent
needed to prevail on today's challenge conditions have obviously never put on their shoes and tried to compete with the talented kids of today.

The game changed s bunch in the early 70 s when non red label urethane lane finish replaced lacquer.  It was this change that brought Roth and Holman to the fore front, and a bunch of lessor power players who followed.  Holman was smooth to the line, unlike Roth, but he was a high rev player who took carry to another level with the soft polyester balls that pretty much made hard rubber obsolete during this time. 

One thing I think people don't realize is that the top centers in hot bed bowling cities like St Louis, Detroit, Seattle and LA, were very high scoring even back to the 60's.  Not like today because of the carry, but easy to the pocket.  The modern scoring explosion started with the introduction of the soft polyester balls.  In our city association there had been 2 800 series in the history of the assoc prior to 1975.  In the 1975 season their were 6.  My own average went from 199 to 214 when I switched to polyester that season.  Around the city the number of 200 averages went way up.  Our city was not near as high scoring as Seattle or Portland.  I remember bowling a team tourney in Portland about that time where we averaged 220 per man over 12 games.  We finished 3rd. 

By the 80s when urethane balls came in and walled up shots were legal as long as the oil didn't go past 24 feet, averages continued to climb.  I was usually close to 220, and hit 225 a couple of times during the 80s.  It was also during the 80' that power began to get even more rewarded that accuracy.  Roth and Holman had paved the way, but by the mid 80's a bunch of guys with more wrist cup  and less accuracy were winning on tour.

Maximum was 24 feet, unless oil was applied evenly gutter to gutter.  That rule was changed in 1989 to system of bowling that required 3 units of oil out to the gutter.  24 foot rule was ridiculous because there was no requirement to strip, thus lanemen walled them 10 to 10  then let the carry down build up for a week or more.