1. ## Can you lose 4 trades in the row trading manually?

Subj + I cannot, so far at least

Forgot how that system named exactly playing just doubling your
lot size.

1. 0.2 if lose, next 0.4 if lose next 0.8 if lose next 1.6 lot == win back to 0.2
lot and so on.. Like in casino, that's why those guys set MAX bet
so you cannot win constantly..

Not sure about stupid robot, but you have to be total moron to
lose 5 trades or so in the row, and, if you are a moron then
flip a coin and don't forget to set stop loss and take profit points
base on the chart technical’s.. 50/50 chances even if you flap a coin
and doubling your lot size, SL and TP will take care of the rest

Fair enought?

Can that be programmed? Don't think so. cause most robots lose money..

2. This is system what you are talking about is Martingale System and you can lose money specially EA programmed with martingale system.

3. Martingale is gambling, and if you think losing 4 trades in a roll is impossible, take a look at this derren brown's clip:

YouTube - Derren Brown - The System - Coin Toss

He tossed a coin and it gets head 10 times in a roll. Though after the show he explain that he took 9 hrs to film this show and the probability of getting 10 heads in a roll.

And doubling the lot size doesn't work effectively, it should be 2x +1 , ie. 1,3,7,15,31,63.Because when you lose 1, you need 2 to recover the loss and 1 to get the extra profit.