There's absolutely no need to get up close and personal and there's certainly no need to go using cleaning creams. The same technique works for gutters, soffits, fascia boards, cladding and conservatory roofs.
I expect that everybody has a different way of working.
Now I'm probably one of the least experienced people on the forum, but I've done a few of these jobs. After each one I've asked myself what I could have done to make the job quicker and easier. This is the system I've come up with.You can use it as a starting point and improve on it if you can. The technique works for all non-window jobs I've come across.
1 - Soak with a weak solution of tfr/truck wash/ecover in pure water and agitate with a brush to loosen all the dirt. The easiest way is simply to dip a brush into a bucket of tfr and brush it on. Make sure that you scrub every single square millimeter! This is probably the most important and physically demanding part of the job. The more effectively you do this bit, the easier is the rest of the job.
If it's a BIG job, do it a section at a time to make sure that the tfr doesn't dry.
2 - Rinse off with a hose using the customer's outside tap. As long as you did step 1 well, the dirt will simply get rinsed right away. No more scrubbing should be needed.
3 - For a glass conservatory roof, finish with pure.
Here's a video of Alex of WCR using pretty much the same technique on gutters:
uk.youtube.com/watch?v=NuOkIOfP-B0See the technique? Brush it on. Rinse it off.