JACKSONVILLE – Doug Marrone's doing his best to provide insight.

That has been a theme during the Jaguars head coach's first few media availabilities of 2017 organized team activities, and it was a theme Friday. One insight Marrone shared again Friday:

What's going on at EverBank Field during this unpadded period matters, but there's a limit to how much the work really says about the '17 Jaguars.

"We haven't practiced," Marrone said early Friday afternoon following OTA 6 at EverBank. "I know you guys look out there and you think that's practice … I don't. I don't call it practice. I really don't.

"I don't, because from a physical standpoint, I don't know if we can tackle. I don't know if we can hold on to a ball when we get hit. I don't know how we're going to react when it's a live rush and the guy can hit the quarterback how the quarterback's going to react. There are a lot of things that go into my mind.

"Maybe I'm not right. Maybe I'm wrong. I'm not saying I know all of this stuff, but that's kind of how I look at it."

Marrone said that makes assessing progress from any position or group difficult.

"We're not playing with pads," Marrone said. "To say, 'Hey, we look great and we're ready to go' – I don't know that until we have pads on."

Marrone on Friday said OTA practices are important mentally and fundamentally because such concepts shouldn't be being taught in training camp in late July.

"As far as footwork, technique and what they're doing …" Marrone said, "yes, there are some things I'm seeing that I'm glad we don't have to work on because if we do have to work on some of those things now, we're going be in trouble. We're not going to get there. …

"When we put the pads on, we can't go back to the things we're coaching now: fundamentals, assignment and drills. The more we have to go back and coach those things in training camp the harder it's going to be to get where we want to be."

Also around the Jaguars Friday:

*Marrone addressed Thursday's Jaguars OTA Topic of the Day – that last year's starting center, Brandon Linder, is taking extensive repetitions at guard. Linder played guard in 2014 and 2015 before moving to center last season. Marrone said the team also is working A.J. Cann at both guard positions, and also working linemen such as Tyler Shatley, Chris Reed, Luke Bowanko and Patrick Omameh at multiple spots. "We're trying to find the best five coming in," Marrone said. "The good thing is when Brandon played guard here he was one of the top guards in the league and when he played center he was one of the top centers in the league. We have flexibility to take a player, not lose anything at either position and see what the other players are doing from a mental standpoint of being able to handle it." …

*Marrone also addressed Cann specifically, saying "A.J. caught lot of heat last year. I'm not going to get into whether he played better or less or whatever. But in my opinion A.J. is a good enough player to play in the NFL. He's done a lot of good things. He has a long way to go, but he has great potential to do that. I think he can play winning football for us." …

*Marrone also addressed comments made by linebacker Telvin Smith early this week, comments in which Smith said – among other things that he believed the Jaguars weren't progressing as quickly he hoped. "Obviously, he's someone who has leadership qualities on the defense," Marrone said. "I think you have to be careful when you're talking about that. You need to address the players. You don't want to try to send messages through the media, if that's what he was doing – which I don't think he was. I think he was trying to show some leadership ability, but I think there are better ways to do that.''

*Marrone said OTAs are absolutely important for giving players an understanding of the level of conditioning necessary in training camp. "I'm always looking for tough days, honestly," Marrone said. "That way, we get ourselves acclimated, and get ourselves to push through it. We have to just kind of remember that when we're done with the mandatory minicamp, in about five weeks when we come back … hey, the heat's going to be turned up a little bit more. It gives our guys a lot of incentive to come back in shape so we can get a lot of things done." …

*Marrone said the team has reduced mental errors in recent practices. "It's something we've been addressing, and it has been getting better," he said. "That's what I look at." …

*Defensive end Calais Campbell and safety James Sample, both of whom missed practice Thursday for personal reasons, practiced Friday. …

*Wide receiver Dede Westbrook, running back T.J. Yeldon, tight end Marcedes Lewis, tight end Neal Sterling, cornerback Tyler Patmon, defensive tackle Stefan Charles, cornerback Aaron Colvin, safety Tashaun Gipson and safety Barry Church did not practice Friday with most of those players working on the side. …

*Rookie running back Tim Cook and rookie wide receiver Kenneth Walker are not in attendance because of NCAA rules prohibiting players from participating in offseason programs until their schools finish spring classes. …

*Left tackle Branden Albert continued to remain away from OTAs. The Jaguars acquired Albert in a trade with the Miami Dolphins in March and he has yet to participate in the team's offseason program. Offseason activities are voluntary until the team's mandatory June 13-15 minicamp. …