spot betting = more pressure
It doesn't have to.
I would say this is function of the fact that spot betting means betting less games yet somehow the bettor feels he must still be risking the same amount as if he were betting more regularly.
It becomes another excuse to bet more than usual and tends to not work out.
There can be safety in numbers, and spot betting, to some degree (from a near term standpoint) deviates from that. If you bet more than usual just because you are betting less often that equals pressure.
If you feel your spot bet is a better bet than other times, and that's why you raise the bet amount, it will still equal the pressure you are talking about.
Instead, I would suggest keeping that spot bet reasonable and use patience to take longer to get you fill of bets in. It can be tough to do, if you can remember why you chose to spot bet to begin with, it can help you stat the course.