Yes Mamy - have tried most of the DIY - I never heard of it until a visitor was at sista's - he got it somewhere - will get his number and ask where he got it.
There is a split between my guttering and neighbours - with result when it rains it pours vehemently between the split and back onto our brick walls - I am afraid of wall becoming damp.
I've found the best way to bodge a leak in a gutter is to use sheet lead. Clean and dry the affected area, coat the area with silicon, then nail the sheet lead into the bottom of the gutter, using cooper clout nails.