To tight mark or not to, To close down or not to

Is there a basic rule to follow the using Oppostion Instructions for tight marking, closing down. I never tight mark players with pace acceleration over 15 -16, but tight mark players with pace/acceleration of 5 -10 and close down players who provide the most assists. However sometimes this dosent appear to work and the oppositon player gets by mine. What sysyems do you use for this

You really can't have a hard and fast rule.

You need to look at the formations, the players and decide from there.

In general something like a 442 lining up like for like I would close down the opposition MCs + wingers (unless they were really quick), not the forwards though as if they step past your DCs they have a free shot at goal.

In terms of tight marking I would tend to look for slow strikers that play with the back to goal.

Other formations, not like for like I would take on a case by case basis but I always tend to look to close down the passers and tightly mark the outlet balls.

And of course, your own players. I have a pacy defender who can mark very well, so I definitely consider him for marking roles on pacy strikers. My formation tends to have either 2 CMs, or 3 CMs, usually no DM, or AM. So I pretty much ALWAYS close down the opposition's two MCs (very very rare to face a formation that doesn't have two MCs I find), its just how I want my team to play. All 6 attacking opposition players will be put on the weaker put.

Against a 4-1-2-1-2 or a 4-5-1 variation I will consider playing with a DM because it cuts off a very simple yet effective passing lane, from DM to ST.

I never use the tight marking/closing down instruction in "opposition instructions" section simply because it applies to every player that was on that specific player and you simply can't predict who is going to be on the player... for example, if you use close down on a slow but creative AM and your fast CD happen to be the closest to him, then he'll charge toward the AM, leaving his slower partner behind, then opposition poacher run up (which your fast CD supposed to be on), opposition AM make a through pass as your fast CD almost on him, now only the fast poacher and your slower defender contending for the ball... if you're lucky your defender can get a sliding tackle on the poacher before he can get a shot off, if not the poacher will get a clear cut chance...

It's better IMO to just use the marker on player instructions