One of the key messages from the recent Ashes series, according to the media anyway, was that "pace rules". The primary difference between Australia in England in 2013, and then England in Australia in 2013-14, was seen by many to be the fast bowling of Mitchell Johnson, the eventual Man of the Series.

His raw speed (admittedly combined with far greater control over direction than in some previous years) was claimed by many commentators to be the deciding factor in Australia's transition from a 3-0 series loss to a 5-0 series victory in the space of a few months. It was not uncommon to hear comparisons between the speed of Johnson and that of the legendary Jeff Thomson in the 1970s.

But what does "pace" or "speed" actually mean?

In recent times, the proponents of various fast bowlers often base their argument around the figures generated from the speed gun. While the overall speed readings are very interesting, it would appear misleading to rely solely on these figures, as they don't actually come close to telling the whole story about how "fast" a batsman will consider a bowler to be. It was not uncommon to hear commentators literally jump with excitement about the extreme pace of a certain Johnson delivery that caused a batsman significant problems, only to then see a speed-gun rating show that it was actually slower than the previous ball that the batsman had played easily.

In the most recent Ashes series, a recurring theme among the commentators was that James Anderson was tired and "lacking a yard of pace" compared to his spells during the English summer. This would appear to be supported by raw statistics that show he took 22 wickets at an average of 29 in England, whereas in Australia he took 14 wickets at nearly 44. However, a review of his average bowling speeds across both Ashes series makes for interesting reading.

In the first Test in Nottingham he averaged 84.9mph; in the fifth Test in Sydney he averaged 84.5mph. Anderson's average bowling speed per innings was remarkably similar across the ten Tests, and only varied around three miles an hour. His highest average speed per innings was actually in Perth, the "eighth" Test, where he averaged 85.5mph. Whatever the reasons for his relatively poor performance in Australia, it can hardly be argued that it was due to him "lacking a yard of pace".

At this point, I understand that many readers will no doubt be striking their foreheads on their monitors and shouting, "You idiot - he is a swing bowler and doesn't rely solely on pace." This is precisely why the speed gun is an unreliable measure. Ultimately, does it matter how we judge the "pace" of opening bowlers? Unfortunately, and this was primary reason for this article, the speed gun is becoming a concerning aspect of team selection. It was only a few weeks ago that Australian coach Darren Lehmann outlined that bowlers need to be bowling at 140kph to be considered for the Test team. Clearly the speed gun is becoming a determining factor that helps fast bowlers get selected.

There is a former Australia Test opening bowler, still only 27 years old, who has taken 202 first-class wickets at an average of 25.10, and took 5 for 105 in his last first-class match, but appears to have been forgotten about in terms of national selection. Trent Copeland doesn't bowl at 140kph, and therefore doesn't appear likely to add to his three Test caps. However, players who have faced bowlers such as Copeland, Chadd Sayers or even Glenn McGrath will note that they are "faster" than they appear. A few years ago McGrath's deliveries were measured as being slower than those of Greg Blewett. However, if you asked opening batsmen which one was "faster", without any reference to the speed gun, Blewett would have struggled to gain a vote.

Phrases such as "hitting the bat hard" or "bowling a heavy ball" are used to describe bowlers who manage to bowl "faster" than someone with an identical speed-gun rating. From discussions with many batsmen over a number of decades, I have concluded that certain bowlers seem faster than others because they force batsmen to make a late adjustment when the ball is not quite where they expect it to be.

From the point when the bowler hits his delivery stride, the batsman starts moving into position to play a shot. With only half a second or so from the bowler letting it go until the batsman plays the ball, the batsman has to move on instinct into the correct position. A bowler who delivers a "heavy ball" is generally one who consistently hits the bat slightly higher than expected, thus leading to a batsman feeling a less than ideal contact and subsequently having less control over the shot.

Likewise, if a bowler has an unusual or strange action that prevents a batsman getting an early sighting of the ball, they will appear faster. The great South African Mike Procter was rated by Tony Greig as one of the "top five" paceman of his era; Greig thought Procter bowled at a similar pace to Andy Roberts, John Snow, Dennis Lillee and Jeff Thomson. However, it was interesting that in one of the early speed tests, conducted in 1979, Procter came second-last among 12 bowlers, and only managed to beat Pakistan medium-pacer Sarfraz Nawaz. At that time Procter was in his early 30s, but he played first-class cricket for another decade, and he opened the bowling for the WSC World XI.

While the actual speeds recorded in this trial cannot be fairly compared to those of current bowlers, due to differing measuring techniques, the comparative nature of the test showed that Procter was a long way behind Thomson, who led the field. However, opening batsmen of that era would clearly not agree that Procter wasn't a genuine fast bowler. He is an example of how speed can be disguised, as his "wrong foot" action meant that batsmen were not picking the ball up early.

When Brett Lee was bowling at 135kph, batsmen perceived him as far "slower" than McGrath at the same velocity, as Lee had a flat and predictable trajectory. This meant that a batsman was in position to play a shot earlier than against McGrath, who tended to achieve extra bounce or movement off the seam that forced batsmen into a late readjustment. This then made the batsmen perceive the bowler as being faster than a pure speed reading would have given them cause to do.

It would appear clear that Anderson's lack of effectiveness in Australia related more to his inability to move the ball consistently, rather than him being tired and "losing pace", as some commentators argued. Speed is not easily defined, and success does not always equate to high speed-gun measurements. The current No. 1 bowler in the world, Vernon Philander, is a great example of this, but it appears that he would not get a run for Australia as he bowls at a "mere" 130kph.

I hope the Australian selectors and coaching staff are willing to recognise that the speed gun alone does not define the effectiveness of an opening bowler, or just how "fast" he may be.