deriv LSK ETT STT aSTA ALPH OLDHOMEPAGE NEWHOMEPAGE
labh लभ् + hard /iT'
→ labh लभ् + sIy सीय् + /iT' by liGassIyuT
→ labh लभ् + sIy सीय् + /a by iTot
→ **labha- लभॱ + Iy ईय् + a अ by liGassalop...
→ **labheya लभेय
Besides deleting the s स् of /yAsuT and /sIyuT, this rule also deletes the s स् that suTtithoH might have added to the ending itself —
hard /liG /tip → /yAsuT + /tip → yAs यास् + stip स्तिप् → yAs यास् + st स्त् → yAsst याःस्त् → **yAt यात्
dviS द्विष् + hard yAsst याःस्त् → **dviS- द्विष् + **yAt यात् → **dviSyAt द्विष्यात्
bhU भू + hard yAsst याःस्त् → **bhava- भवॱ + hard yAsst याःस्त् → **bhava- भवॱ + iysst इय्ःस्त् → **bhavet भवेत्
labh लभ् + hard sISTa सीष्ट → **labha- लभॱ + **Ita ईत → **labheta लभेत
hard /Atmanepada example —
hard /liG /ta
→ sIyta सीय्त by liGassIyuT
→ sIysta सीय्स्त by suTtithoH
→ Iyta ईय्त by liGassalop...
→ Ita ईत by lopovyorvali
→ **Ita ईत "he would (get)" as in **labheta लभेत, **dviSIta द्विषीत
labh लभ् + hard liG /ta
→ **labha- लभॱ + /ta
→ **labheta लभेत by AdguNaH
→ !**labheta लभेत "he'd get"
rule yAsuTparasm... adds yAs यास् before flats, but this rule removes the s स् —
**paTha- पठॱ + /liG /jhi
→ paTha पठ + yAs यास् + /jhi by yAsuTparasm...
→ paTha पठ + yAs यास् + us उस् by jherjus
→ paTha पठ + yA या + us उस् by liGassalop...
→ paTha पठ + iy इय् + us उस् by atoyeyaH
→ !**paTheyus पठेयुस् "they would recite"
Why do we say "nonfinal" s स्?
Because the s स् of /s''' /jus /thAs stays. See flat hard liG and bent hard liG for examples.