No player is perfect. Even the world's greatest stars with bags of experience can learn something. The trouble is, the greater the player, the greater the coach needs to be to improve the star.
This screen enables you to manage the activities of your coaches and assess their ability to effect improvements in your squad. It's split into three segments to make it easier to navigate: coaching attributes, assignments and summary.

Coaching Attributes
The window in the middle of your screen lists all of the coaches at your disposal along with their attributes rating out of 20. Each of these ratings corresponds to a coaching discipline, so it pays to match up your trainers to coaching activities that suit their skills. The better a coach is, the more a player is likely to improve under his tutelage.
Also in this panel is the Assigned category which shows the number of coaching disciplines each coach is assigned to. Details of their assignment are given in the assignment column to the right.
To simplify your options here you can click the Auto Assign All button which will select your coaches for each training category according to their greatest strengths. Clear Assignments enables you to start from scratch and re-assign coaches either automatically or by using the assignments panel.
Once you have your coaches assigned you can click Show Filters, which opens up a new panel on the right enabling you to sort your list of coaches and display them according to the activities they are active in.

Assignments
The assignments panel not only enables you to see who is taking which elements of your training, but it also gives a simple overview of the ability of your coach in that discipline.
Once again the categories of coaching skills are shown, with the disciplines the highlighted coach is active in shown with a tick. To ask your coach to take part in every coaching discipline you can tick All, otherwise you can select and de-select which assignments you give your coaches by clicking to the left of the skill set name.
For whichever disciplines the coach is active in a star rating appears to the right of the skillset name. This indicates an overview (five stars being the maximum) of a coach's ability. If you feel you need more effective coaches you can either approach them through the Search: staff screen or put up a job advert on the Job Centre screen.

Summary
This screen enables you to judge the effectiveness and workload of your coaches and ensure you are neither spreading your coaches to thin by asking them to do too much nor under-using them by asking them to do too little. Note that by retaining too many coaches you may be wasting money that could either be better spent elsewhere or saved to enhance your chairman's confidence.
The categories are clear enough, listing the training skillset along with how many players are assigned to regimes that cover each set and the number of coaches working in each area.
The two key factors here are the last ones: workload and rating. Workload, clearly, shows how much your coaches are being worked. If the workload is light for a given category, you can afford to have fewer coaches taking part in the activity. You may be better off reassigning them to another task where you have less coaches assigned. You can do this in the assignments panel on the top right of the screen.
Of course the quality, not just quantity of coaches' work is crucial too. The rating shows the overall ability of the coaches assigned in each discipline. To improve this rating you should reshuffle your coaches to assign those best equipped to get more out of your players.
If you simply haven't got enough quality coaches in certain disciplines then there are two key options open to you. Either you should modify the training schedules you are giving to you players, which may have a profound effect on the way your players play, or you should draft in new coaches. If you decide, for instance, that you haven't enough quality defensive coaches, but you have better attacking ones, you may want to assign more players to attacking training and look at adjusting your tactics to suit the developing skills of your players. You can use the Tactics screen to make these changes.
The other option is to draft in new coaches. Again, this can be done by either approaching them through the Search: staff screen or by putting up a job advert on the Job Centre screen.
It's worth spending time to put an effective backroom team in place so you don't have to concern yourself with the ins and outs of your players' training. This will not only give you more time to spend on more important issues, it will also mean your players are in good shape come match day.