Leeds boss Marcelo Bielsa has sent a member of staff to watch every team they have played this season train.
Bielsa, 63, called an unscheduled news conference on Wednesday as the Football Association and English Football League investigate the 'spy' saga.
Before Friday's Championship win over Derby, the ex-Argentina manager said he sent someone to watch the Rams train.
"I observed all the rivals we played against and watched the training sessions of all opponents," he said.
"All the information I need to clarify, I gather it without watching the training session of the opponent, so why did I send someone to watch them? Just because I thought I wasn't violating the norm. I gathered information that I can obtain in another way.
"We feel guilty if we don't work enough. It [watching the opponents train] allows us to have less anxiety and in my case I am stupid enough to allow this kind of behaviour."
The Argentine said what he has done is "not illegal" but accepted that he will have to "respect the sanctions" that the FA or EFL may bring against him or Championship leaders Leeds.
'I feel ashamed to tell you all this'
In a remarkable news conference, Bielsa showed journalists how much preparation and analysis he and his staff carry out on each opponent before every game by using a PowerPoint presentation.
He said that analysis of each of their opponents' previous matches takes four hours per game.
Bielsa showed Leeds had information on the percentage of games in which Derby used certain formations, which players were used in which positions and formations they had struggled against this season.
"I feel ashamed to have to tell you all this," added Bielsa, who also displayed detailed information on some of the Rams' players.
More than one hour after first starting his presentation, he concluded: "I'm not cheating. I knew everything I needed to know."
'I am sitting in a coaching masterclass'
Leeds said the news conference would be in relation to last Friday's spying incident and that Bielsa would be speaking when they contacted members of the press at 13:00 GMT, but offered no further information as to what it would be about.
Some thought that Bielsa intended to use the conference to resign, prompting Leeds defender Pontus Jansson to tweet a journalist asking if it was "already 1 April in your office?"
Here is some of the reaction from the journalists who attended:
'It's unethical' - how did we get to this point?
A Leeds staff member was seen acting suspiciously outside Derby's training ground last Thursday, after which Bielsa said he instructed the unnamed employee to carry out the task.
Derby boss Frank Lampard described the incident as "bad" and "unethical", claiming it had "disrupted" his side's preparation for the match.
Leeds won 2-0 at Elland Road and are four points clear at the top of the Championship.
On Saturday, Leeds issued a statement apologising to Derby and subsequently reminded Bielsa "of the integrity and honesty" of the club.
The EFL has since written to Leeds, requesting their observations and suggesting the action "appears to contravene the club's charter" which all 72 EFL clubs agreed to in the summer of 2018.
'What rule has he broken?' - analysis
BBC Radio Leeds' Leeds United commentator Adam Pope
I arrived at Thorp Arch with a swirl of social media and texts bombarding my phone from distraught fans and erroneous online reports adamant that Bielsa was resigning.
Prior to the briefing I'd heard he'd taken training so that allayed any major concerns about him walking out.
Once in the packed and expectant press room, Bielsa was already waiting with his translator, Salim Lamrani.
Unusually, he was sat to one side with an array of folders, smart boards & data. Unbeknown to us, he was about to deliver a masterclass of coaching while schooling those who had called him a cheat in the 'Spygate' affair.
It was a supreme performance, pure theatre but from a man who does not want to be the star of the show.
His diligence and dedication to improving Leeds United was measured in the classroom on Wednesday, and it is reflected in the respect he has for the competition and his opponents by the extra homework he is prepared to do.
Lesson over, he walked out of the door but not out of the club.