Thanks to John Terry, the world now has irrefutable proof that despite its possible glitches, GLT (Goal-Line Technology) must be superior to GLH (Goal-Line Human).

And if a GLT system is adopted in July, MLS commissioner Don Garber has already stated the league would implement it as quickly as possible. That would mean the second half of the season would be played under different officiating conditions as the first half, but given the viral nature of such incidents, he and the league don’t have much of a choice. They can’t risk a playoff game or MLS Cup being marred by a flubbed goal-line call, or at least leave the decisions up to mere humans if a technological system has been approved.

England beat co-host Ukraine, 1-0, Tuesday on the final day of group play in the European Championship. The victory moved England to the top of Group D and knocked out Ukraine, but the result almost took a back seat to an officiating error that cost Ukraine an equalizer.

When Terry cleared a shot by Ukraine’s Marko Devic that had fully crossed the line, but barely, not 10 yards away stood the GLH. Technically, he’s a “fifth official,” one of two stationed on the goal-line to judge such incidents. For whatever reason, he didn’t signal a goal even though television replays showed the ball passing all the way past the goalposts -- and thus the goal line, since by rule they must be the same width -- before Terry volleyed the ball clear.

The curse of replay cameras, particularly those that slow down the action, is they don’t accurately represent what the human eye can discern in real time. The time lapse between the ball crossing the goal line and Terry’s foot hacking it away was a fraction of a second, and though a freeze-frame caught the ball an inch or so beyond the posts, the fifth official’s eyes didn’t.

So why doesn’t FIFA approve the use of video replays for goal-line incidents, rather than the two imaging systems, GoalRef and Hawk-Eye, being tested by the International Football Association Board, which implements rule changes? There are technical issues as well as political ones, but one side effect would be creating more problems and controversies than those a goal-line camera system might solve.

What FIFA fears are instances such as the buildup to the Ukraine “goal,” in which Artem Milevskiy was offside when he ran onto a ball before he crossed it to Devic. While a camera sited along the goal line -- another form of technology the world governing body absolutely refuses to consider -- probably wouldn’t catch the offside, wider angles very well could. The howls of protest of the defending team once replays were shown would be in regards to a blown offside call, not whether or not the ensuing shot had crossed the goal line.

One might argue that FIFA, as does the NFL for video replays, can stipulate what can be reviewed and what can’t. And that’s utterly impractical, for the NFL is a 32-team, wildly profitable, self-administering fiefdom. It can pass rules and tweak them and change them with impunity, as it has done numerous times since adapting the initial version of replay in 1986. FIFA has, literally, a whole world to administer.

If FIFA had used instant replay at the 1986 World Cup, and thus disallowed Diego Maradona’s handball goal against England, he and Argentina would still be claiming a “video conspiracy” had been formed to wreck their chances of a world championship, whether or not they’d gone on to win the trophy. And I don’t mean to single out Argentina; the top national teams and most powerful clubs would lead the protests in borderline cases, and that’s a migraine FIFA executives just don’t want.

FIFA has enough trouble keeping teams and national federations in line as it is; if cameras policing goal-line incidents in every professional match were also recording jersey grabs, body slams, and leg whips not disciplined by the game officials -- not to mention botched offside calls leading up to goals -- so many protests and objections would be filed the game would grind to a halt. There would be extreme pressure to either expand video surveillance of matches, or drop technology altogether.

The imaging systems reveal, nearly instantaneously, only if a ball has passed beyond the posts and the goal-line. (Demands for rigorous maintenance and recalibrations will be bothersome but tolerable.) If a system passes the tests, FIFA will have a method -- in theory, anyway -- of addressing a major problem without triggering unmanageable aftereffects. Regardless, it should also keep the fifth officials, and perhaps empower them to help the referee and referee’s assistants to police action around the goal, where fouling is rampant.

It must be said that match officials, including the GLH, got the call right when Antonio Cassano’s header in the Italy-Ireland match Monday hit the crossbar and landed beyond the goal line before being cleared. Maybe balls hitting the ground are easier to call, since a ball on the ground is much closer to the goal line than one in the air, but if that’s the case, how could Frank Lampard’s shot in the 2010 World Cup get nearly a yard beyond the goal line before being scooped clear by Germany keeper Manuel Neuer without a goal being awarded?

While the cries for GLT grow more strident, and adoption of a system is regarded by many as a foregone conclusion, what happens if the tests determine neither system is reliable enough? The second phase of testing is being conducted in various stadiums, in differing lighting and weather conditions, during actual games to determine reliability. It was used in the England-Belgium friendly in late May.

Scorn will rain down on the IFAB if its report next month says neither system is reliable enough to be adopted, and FIFA won’t escape criticism, either. Yet for all competitions, and all leagues such as MLS, there can’t be a half-measure that works most of the time. The solution has to be just that.