I have five strategies that contain MTF on forward demo test but so far only one has opened a position and unfortunately failed to close it. This may be nothing to do with MTF and maybe something to do with the recent IG demo server crash. I will wait for IG/PRT to let me know.
The down side to MTF is that it can just add extra filters that mean that trades may be higher quality but you get less quantity. Great in real life but not so good for testing confidence. I like longer time frame trading so it could take me quite a while to fully test out the benefits of MTF. Maybe others who like the cut and thrust of minute and second trading have different experiences.
