Viva51, it is tricky to estimate the need to cement (light routine=maybe, hard routine=must), but usually some cementing is preferable just to be sure. In your case cementing was clearly needed if you lost some gains.
Anyway, if you lost some gains I am sure, that you will quickly gain them back.
OK, that what I wrote about the location of thumb. Well lets say, that I didn’t think it through. When I personally jelq, I often jelq side grips (thumb on the side) with just my right hand. Of course there is no need to do that what I wrote if you do it with both hands. I noticed this error too late to correct it.
Still, changing the position of OK grip towards or outwards produces pressure a little differently and so it is good to variate it a little bit.
Thumb on the side(s) concentrates pressure to the two main chambers (corpus cavernosum) and that is why it seems to be best whether it is about girth or length gains. Anyway without knowing exactly how jelqing moves blood in penis (jelqing haven’t been modelled as far as I know) it is good to jelq with a mix of side and up grips
to ensure the right result.
Keep soft tissue soft.