I dont think that it would be unreasonable. He should be able to understand, Im sure that he would need notice as well. Maybe it would help if you phrased it that way, that the two of you should start giving 12 hr notice to eachother. Or at least a 2 or 3 hour window instead of cable guy times (sometime between tuesday and thursday!). It seems like he has a pretty concrete arrangment for his part of the week, but Im just thinking that it might seem a little less confrontational.
I guess I gave the wrong finger to the wrong man...