Overcast May days with rain in the air and helpful green-tinged pitches are not the best conditions to judge the potential of embryonic England pace bowlers.
If the opposition are Bangladesh, who have recorded only three wins in their 68 tests, a true assessment becomes even more difficult.
Such considerations, though, bore little weight with the spectators hurrying through the showers to watch Steven Finn go through his paces in the recent two-test series.
The gangling, 21-year-old Middlesex fast man provided full value with nine for 187 at Lord's and six for 81 at Old Trafford. But, with an Ashes defence in Australia looming later in the year, it was the style rather than the statistics which raised heady expectations.
One of the tallest players to represent England at 2.01 metres, Finn runs in with an athletic, relaxed approach allowing him to get close to 145 kph without strain.
His delivery stride brings him side-on with a high left arm and the only obvious flaw in a supple, biomechanically sound action has been a disconcerting tendency to sprawl on to the pitch after releasing the ball.
The consequent accuracy, life and lift have prompted comparisons with Glenn McGrath, who runs Dennis Lillee close as the best of the Australian pacemen, and the elongated West Indian Curtly Ambrose.
Mindful of Finn's youth and the appalling injury toll suffered by fast bowlers by all test nations in recent years, the England management have been quick to dampen expectations.
Finn will miss the forthcoming five-match one-day series against Australia to undergo a strength-and-conditioning programme and coach Andy Flower said he did not want to make premature comparisons with McGrath, whose test haul of 563 wickets is the highest by any fast bowler.
"Comparing him to other fast bowlers, to me, is not useful," Flower said. "He has a lovely action...he has very good control for a 21-year-old fast bowler. It is a great start for him but he also realises that he has scope for learning and progress."
Finn's maturity and ability to learn were evident during a promising debut in the away series against Bangladesh in March on pitches specifically designed to nullify the England fast bowlers and assist the home team's spinners.
He has already represented Middlesex for five years after becoming the youngest debutant since Fred Titmus, who went on to represent the county in four decades. His mentor is the former Middlesex and England fast-medium bowler Angus Fraser, a past master of unrelenting accuracy, and his hero is McGrath.
"I certainly can put on more pace and it's something I'm looking to do but I'm not going to force it," Finn told reporters at Lord's.
"You have to be clever and learn when to try and bowl quick. McGrath is someone I've always idolised, the metronomic control of line and length is something all fast bowlers strive to achieve.
"Everyone wants to combine pace with that control which McGrath had. In the early part of his career he had that pace and in the later part he needed to learn how to be smarter with the ball; the way he adapted throughout his career is something I really respect."
Wickets at Lord's in May are no reason for excessive celebration. Ed Giddins took five for 15 in an innings against Zimbabwe 10 years ago but played only two more tests. Sajid Mahmood has failed to fulfil the promise he demonstrated with reverse swing at high speed against Sri Lanka in 2006.
Last year Graham Onions drew comparisons with McGrath, and a host of execrable puns from the headline writers, with five wickets in an innings againstn the West Indies. He is currently sidelined by injury.
The records of tall, young England fast bowlers poised to make their Ashes debuts before hostile crowds in Australia's unforgiving climate are discouraging.
David Larter, who was as tall as Finn, made two tours in the 1960s without playing a test. Alan Ward, who excited equally high hopes, returned home early after injury on the 1970-71 tour.
On the plus side, Bob Willis, who replaced Ward on that tour, performed with credit in a winning team and went on to join Frank Tyson, Fred Trueman, and John Snow as one of the four great post World War Two England fast bowlers.
England captain Andrew Strauss, mindful of the importance fast bowling has played in England's rare successes in Australia, recognises what an asset Finn could be while echoing Flower's caution.
"There's a lot of water under the bridge before then," he said. "But he's obviously got some great attributes, his height and a pretty clean action.
"Early in your career it's fantastic to get wickets and show you belong at this level."