Yes, I don't receive many yellow / red cards with my Dortmund team. I can't tell you the figures right now because I'm not at home but I will check & let you know
As for the Team Talks, I almost always used Assertive & sometimes Calm. Depending on the situation of course. If losing or winning without convincing, I would say 'Not happy with the performance' & if winning 2-0 usually I tell them to not be complacent.
However, recently I stopped doing Team Talks, both pre-match & in Half-Time & I noticed that the team performs better. Let me give you 2 perfect examples:
German Cup Final vs Bayern. Losing 2-1 at H-T, in the 2nd half we score twice to make it 3-2 & then Bayern equalise in the 93rd minute. I win it in extra time 4-3 with 10 men given that one of my players got injured & I had used all subs. I didn't give a SINGLE TEAM TALK - not in pre-match, H-T & extra time.
German Super Cup vs Bayern. 1-1 at H-T, we win it 3-1 over 90 mins. We literally battered them! Over 60% possession & a lot of clear cut chances. Again, I didn't give a SINGLE TEAM TALK - not in pre-match & H-T.
There were more games of course without Team Talks & in which we won but it's impossible to list them all here. So, from my experience, Team Talks are not really effective, no - sorry! That's just my opinion though of course